The present disclosure is generally directed in some embodiments towards producing metal spherical or spheroidal powder products from feedstock materials including from scrap materials, dehydrogenated or non-hydrogenated materials, recycled used powder, or oversized gas atomized powder.
An important aspect of preparing some forms of industrial powders is the spheroidization process, which transforms irregularly shaped or angular powders produced by conventional crushing methods, into spherical low-porosity particles. Spherical powders are homogenous in shape, denser, less porous, have a high and consistent flowability, and high tap density. Such powders exhibit superior properties in applications such as injection molding, thermal spray coatings, additive manufacturing, etc.
Creating spheroidal metallic powders, especially metallic powders containing Ti, can pose a number of challenges. Achieving the desired spheroidal shape, the desired level of porosity (e.g., no porosity to very porous), and the desired composition and microstructure can be difficult.
Conventional spheroidization methods employ thermal arc plasma described in U.S. Pat. No. 4,076,640 issued Feb. 28, 1978 and radio-frequency generated plasma described in U.S. Pat. No. 6,919,527 issued Jul. 19, 2005. However, these two methods present limitations inherent to the thermal non-uniformity of radio-frequency and thermal arc plasmas.
In the case of thermal arc plasma, an electric arc is produced between two electrodes generates a plasma within a plasma channel. The plasma is blown out of the plasma channel using plasma gas. Powder is injected from the side, either perpendicularly or at an angle, into the plasma plume, where it is melted by the high temperature of the plasma. Surface tension of the melt pulls it into a spherical shape, then it is cooled, solidified and is collected in filters. An issue with thermal arc plasma is that the electrodes used to ignite the plasma are exposed to the high temperature causing degradation of the electrodes, which contaminates the plasma plume and process material. In addition, thermal arc plasma plume inherently exhibit large temperature gradient. By injecting powder into the plasma plume from the side, not all powder particles are exposed to the same process temperature, resulting in a powder that is partially spheroidized, non-uniform, with non-homogeneous porosity.
In the case of radio-frequency inductively coupled plasma spheroidization, the plasma is produced by a varying magnetic field that induces an electric field in the plasma gas, which in turn drives the plasma processes such as ionization, excitation, etc. to sustain the plasma in cylindrical dielectric tube. Inductively coupled plasmas are known to have low coupling efficiency of the radio frequency energy into the plasma and a lower plasma temperature compared to arc and microwave generated plasmas. The magnetic field responsible for generating the plasma exhibits a non-uniform profile, which leads to a plasma with a large temperature gradient, where the plasma takes a donut-like shape that exhibiting the highest temperature at the edge of the plasma (close to the dielectric tube walls) and the lowest temperature in the center of the donut. In addition, there is a capacitive component created between the plasma and the radio frequency coils that are wrapped around the dielectric tube due to the RF voltage on the coils. This capacitive component creates a large electric field that drives ions from the plasma towards the dielectric inner walls, which in turn leads to arcing and dielectric tube degradation and process material contamination by the tube's material.
To be useful in additive manufacturing or powdered metallurgy (PM) applications that require high powder flow, metal powder particles should exhibit a spherical shape, which can be achieved through the process of spheroidization. This process involves the melting of particles in a hot environment whereby surface tension of the liquid metal shapes each particle into a spherical geometry, followed by cooling and re-solidification. Also, spherical powders can be directly produced by various techniques. In one such technique, a plasma rotating electrode (PRP) produces high flowing and packing titanium and titanium alloy powders but is deemed too expensive. Also, spheroidized titanium and titanium alloys have been produced using gas atomization, which uses a relatively complicated set up and may introduce porosity to the powder. Spheroidization methods of irregular shape powders include TEKNA's (Sherbrook, Quebec, Canada) spheroidization process using inductively coupled plasma (ICP), where angular powder obtained from Hydride-Dehydride (HDH) process is entrained within a gas and injected through a hot plasma environment to melt the powder particles. However, this method suffers from non-uniformity of the plasma, which leads to incomplete spheroidization of feedstock. The HDH process involves several complex steps, including hydrogenation dehydrogenation, and deoxydation before the powder is submitted to spheroidization. This process is a time consuming multi-step process, which drives up the cost of metal powders made through these methods.
A method for manufacturing a spheroidized powder from powder previously manufactured from a gas atomization process, the method comprising introducing powder previously manufactured from a gas atomization process into a microwave plasma torch, the powder previously manufactured from a gas atomization process having an average particle size outside of a range for additive manufacturing, and melting and spheroidizing the powder previously manufactured from a gas atomization process within the microwave plasma torch to form spheroidized powder particles having different average particle sizes and a smaller particle size distribution from the average particles size and the particle size distribution of the powder previously manufactured from a gas atomization process.
In some embodiments, the melting and spheroidizing increases the average particle size. In some embodiments, the melting and spheroidizing decreases the average particle size. In some embodiments, the particle size distribution of the spheroidized particles is at least 50% less from 10% to 95% as compared to the particle size distribution of the powder previously manufactured from a gas atomization process.
In some embodiments, a 50 percentile particle size of the spheroidized powder is reduced by at least 40% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. In some embodiments, a 50 percentile particle size of the spheroidized powder is reduced by at least 50% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process.
In some embodiments, a 50 percentile particle size of the spheroidized powder is increased by at least 40% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process. In some embodiments, a 50 percentile particle size of the spheroidized powder is increased by at least 50% as compared to a 50 percentile particle size of the powder previously manufactured from a gas atomization process.
In some embodiments, the powder previously manufactured from a gas atomization process comprise a material selected from the group consisting of metal, metal alloy, titanium, titanium alloy, nickel, nickel alloy, cobalt, cobalt alloy, iron, iron alloy, a ductile metal, a ductile metal alloy, and ceramic. In some embodiments, carbon and nitrogen are removed from the powder previously manufactured from a gas atomization process during the melting and spheroidizing. In some embodiments, the spheroidized powder particles retain the same rheological properties as the powder previously manufactured from a gas atomization process after the melting and spheroidizing.
Disclosed herein are embodiments of a method for manufacturing a spheroidized powder from scrap metal or used metal parts, the method comprising: providing scrap metal or used metal parts comprising a material selected from the group consisting of metal, metal alloy, titanium, titanium alloy, nickel, nickel alloy, cobalt, cobalt alloy, steel, and steel alloy; milling the scrap metal or used metal parts to produce metallic particles within a range of particle volumes pre-determined to be suitable for use as feedstock in a microwave plasma process; and applying the microwave plasma process to the metallic particles within the determined range of particle volumes to form spheroidized powder.
In some embodiments, the determined range of particle volumes can be between 15 and 63 microns. In some embodiments, the scrap metal or used metal parts can comprise a work hardened microstructure that is retained in the spheroidized powder after applying the microwave plasma process. In some embodiments milling the scrap metal or used metal parts can be done without embrittling the scrap metal or used metal parts.
In some embodiments, the scrap metal or used metal parts can comprise Ti 6Al-4V. In some embodiments the scrap metal or used metal parts can comprise alloy elements including Al, Mg, Ti, and/or Cu and, after applying the microwave plasma process the spheroidized powder still includes the Al, Mg, Ti, and/or Cu. In some embodiments, the scrap metal or used metal parts can comprise sharp turnings, saw swarfs, grinding swarfs, grinding fines, and/or wash line fines. In some embodiments, the scrap metal or used metal parts can be selected for the milling to have a size and/or aspect ratio that will result post-milling in metallic particles within the pre-determined range of particle volumes.
Further disclosed herein are embodiments of a method for manufacturing a spheroidized powder having a desired particle size distribution between about x and about y, wherein x represents a low end of the particle size distribution and y represents a high end of the particle size distribution, the method comprising: introducing metallic particles obtained by milling or crushing scrap metal or used metal parts into a microwave plasma torch, a majority of said introduced metallic particles having a volume between about 4/3π (x/2)3 and about 4/3π (y/2)3, and wherein said introduced metallic particles have a collective average or median aspect ratio between 2:1 and 200:1; and melting and spheroidizing the metallic particles within the microwave plasma torch to form spheroidized powder having the desired particle size distribution of about x to about y.
In some embodiments x can equal 5 microns and y can equal 45 microns and the majority of said introduced metallic particles can have a volume between about 65.45 μm3 and about 47,712.94 μm3. In some embodiments, the collective average or median aspect ratio can be between 5:1 to 20:1. In some embodiments, the collective average or median aspect ratio can be between 10:1 to 100:1. In some embodiments, the introducing metallic particles into the microwave plasma torch can comprise introducing the metallic particles into an exhaust of the microwave plasma torch or into a plume of the microwave plasma torch.
Further disclosed herein are embodiments of method for manufacturing a spheroidized a powder from used powder, the method comprising: introducing previously used powder particles into a microwave plasma torch, the previously used powder particles comprising satellites, agglomerations, or contaminants; and melting and spheroidizing the previously used powder particles within the microwave plasma torch to form spheroidized powder particles having the agglomerations, contaminants, and satellites removed.
In some embodiments, the previously used powder particles can comprise satellites, agglomerations, and contaminants. In some embodiments, the previously used powder particles can comprise a material selected from the group consisting of metal, metal alloy, titanium, titanium alloy, nickel, nickel alloy, cobalt, cobalt alloy, steel, steel alloy, a ductile metal, a ductile metal alloy, and ceramic. In some embodiments, carbon and nitrogen can be removed from the previously used powder particles during the melting and spheroidizing. In some embodiments, the previously used powder particles can be formed from an additive manufacturing process selected from the group consisting of laser sintering, electron-beam melting, filament fused deposition, directed energy deposition, powder bed fusion, and binder jetting. In some embodiments, the spheroidized powder particles can retain the same rheological properties as the previously used powder particles after the melting and spheroidizing.
Further disclosed herein are embodiments of a method for producing a spheroidized powder from a feed material comprising dehydrogenated or non-hydrogenated titanium or titanium alloy, the method comprising: introducing a feed material comprising dehydrogenated or non-hydrogenated titanium or titanium alloy particles into a microwave plasma torch; and melting and spheroidizing the particles within a plasma generated by the microwave plasma torch to form spheroidized powder.
In some embodiments, the feed material can comprise titanium or titanium alloy particles processed by a hydrogenation-dehydrogenation (HDH) process. In some embodiments, the spheroidized powder can comprise particles with a median sphericity of at least 0.75. In some embodiments, the spheroidized powder can have a particle size distribution of between 5 and 45 microns at a low end of the particle size distribution range and between 15 and 105 microns at a high end of the particle size distribution range.
In some embodiments, one or more processing variables can be set to create a martensitic microstructure in the spheroidized particles. In some embodiments, one or more processing variables can be set to create an equiaxed microstructure in the spheroidized particles. In some embodiments, one or more processing variables can be set to create at least two regions in the spheroidized powder, each region having a different microstructure. In some embodiments, the at least two regions can include a core portion and a skin portion, the skin portion having a microstructure that can be different from a microstructure of the feed material. In some embodiments the feed material can have a particle size of no less than 1.0 microns and no more than 300 microns. In some embodiments, the feed material can comprise Ti 6Al-4V.
Disclosed herein are embodiments of methods, devices, and assemblies for spheroidization of feedstock materials using microwave plasma processing. Each different feedstock material has its own critical, specialized, and unique requirements for the initial feedstock as well as the processing in a microwave plasma torch in order to achieve a desired spheroidization. Specifically, the feedstock materials disclosed herein pertain to scrap materials, dehydrogenated or non-hydrogenated feed material, recycled used powder, and powders previously manufactured by a gas atomization process, the feedstocks which may require initial pre-processing or specific plasma processing. As disclosed herein, processing in a microwave plasma torch can include feeding the feedstock into a microwave plasma torch, a plasma plume of the microwave plasma torch, and/or an exhaust of the microwave plasma torch. The location may vary depending on the type of feedstock used. Further the feedstock can be selected based on different requirements. Examples of requirements are aspect ratio, particle size distribution (PSD), chemistry, density, diameter, sphericity, oxygenation, hardness, and ductility.
Scrap Materials
Disclosed herein are embodiments of methods, devices, and assemblies for reusing scrap metals/alloys and/or used parts made from metals/alloys (e.g., grave-to-cradle or scrap to premium). In particular, embodiments of the disclosure allow for taking metallic scrap or used metal parts, such as turnings, and without embrittling (such as through the use of hydrogenation or cryogenics) creating a feedstock for a microwave plasma process. Specifically, scrap or used metal parts can be milled to a desired volume of particles of a feedstock or turnings, though in some embodiments may not be milled. The feedstock or turnings can then be used as a feedstock for a microwave plasma process to form a final spheroidized powder, which can then be used in different processes, such as additive manufacturing processes. However, scrap material is extremely difficult to process into a proper feedstock for microwave plasma processing.
In some embodiments the method can include an analysis of the inter-relationship between 1) selection of feedstock size/aspect ratio, 2) a milling approach that breaks up ductile pieces without embrittling steps, and 3) a final desired particle volume, in order to create a desired particle size distribution for specific applications. In some embodiments, the feedstock is embrittled before milling. A user can specify a desired particle volume for the milling of the original scrap, which will influence the selection of the feedstock size/aspect ratio and the milling approach utilized.
The final specific application can be, for example, laser bed fusion which has a particle size distribution (PSD) of 15-45 microns (or about 15 to about 45 microns), or 15-63 microns (or about 15 to about 63 microns) or 20-63 microns (or about 20-about 63 microns), electron beam processing which can have a particle size distribution of 45-105 microns (or about 45 to about 105 microns) or 105-150 microns (or about 105 to about 150 microns), or metal injection molding (MIM). In some embodiments, the PSD can be expressed as the D50 of the particles in the feedstock. In some embodiments, the feedstock is processed through jet milling, wet milling, or ball milling. In some embodiments, the PSD of the feedstock is 15-45 microns, 20-63 microns, 45-105 microns, or 105 to 150 microns. The PSD can be adjusted depending on the powder processing technology such as laser powder bed fusion, direct energy deposition, binder jet printing, metal injection molding, and hot isostatic pressing.
The original scrap or used metal parts can be sharp turnings (e.g., having high aspect ratio, high surface area, thin, or spaghetti-like material, scrap aggregator), saw swarf (high aspect ratio, thin material), grinding swarf (less aspect ratio powder like material), grinding fines, or wash line fines (less aspect ratio, thick or thin plate like material) which can then be broken up into a feedstock of a particular PSD, such as in a milling process, and then microwave plasma processing this feedstock into spherical and dense powders. In some embodiments, the scrap can be 3D printed parts (such as failed 3D printed parts) or castings (such as failed castings). In some embodiments, the input materials can be wash line fine, saw swarfs, grinding swarfs. In some embodiments, the input materials can be used or scrap parts by processes like but not limited to grinding, milling, cutting, or turning.
In some embodiments, high aspect ratio turnings from machining processes are used as feedstock into the microwave plasma melting process to produce spherical powders. In some embodiments, the average aspect ratio of the turnings is 2:1 (or about 2:1), 3:1 (or about 3:1), 5:1 (or about 5:1), 10:1 (or about 10:1), 20:1 (or about 20:1), 100:1 (or about 100:1), or 200:1 (or about 200:1). In some embodiments, the average aspect ratio of the turnings is greater than 1:1 (or about 1:1), 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1). In some embodiments, the average aspect ratio of the turnings is less than, 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1).
In some embodiments, the aspect ratio of a majority of the turnings is 2:1 (or about 2:1), 3:1 (or about 3:1), 5:1 (or about 5:1), 10:1 (or about 10:1), 20:1 (or about 20:1), 100:1 (or about 100:1), or 200:1 (or about 200:1). In some embodiments, the aspect ratio of a majority of the turnings is greater than 1:1 (or about 1:1), 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1). In some embodiments, the aspect ratio of a majority of the turnings is less than, 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1).
In some embodiments, the aspect ratio of greater than 75% of the turnings is 2:1 (or about 2:1), 3:1 (or about 3:1), 5:1 (or about 5:1), 10:1 (or about 10:1), 20:1 (or about 20:1), 100:1 (or about 100:1), or 200:1 (or about 200:1). In some embodiments, the aspect ratio of greater than 75% of the turnings is greater than 1:1 (or about 1:1), 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1). In some embodiments, the aspect ratio of greater than 75% of the turnings is less than, 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1).
In some embodiments, the aspect ratio of greater than 90% of the turnings is 2:1 (or about 2:1), 3:1 (or about 3:1), 5:1 (or about 5:1), 10:1 (or about 10:1), 20:1 (or about 20:1), 100:1 (or about 100:1), or 200:1 (or about 200:1). In some embodiments, the aspect ratio of greater than 90% of the turnings is greater than 1:1 (or about 1:1), 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1). In some embodiments, the aspect ratio of greater than 90% of the turnings is less than, 3:1 (or about 3:1), 5:1 (or about 5:1), greater 10:1 (or about 10:1), greater 20:1 (or about 20:1), greater 100:1 (or about 100:1), or greater 200:1 (or about 200:1).
In some embodiments, the feedstock is tailored to have a volume distribution approximately equal to the volume distribution of the desired PSD of processed powder. Volume is calculated based on 4/3*π*r3 where ‘r’ is the radius of the processed powder. In some embodiments, a majority of the feedstock particles have a volume within a range of about 4/3π (x/2)3 and about 4/3π (y/2)3, wherein x is the low end of the desired particle size distribution and y is the high end of the desired particle size distribution. In some embodiments, substantially all of the feedstock particles have a volume within a range of about 4/3π (x/2)3 and 4/3π (y/2)3. In one example, the volume distribution of the preprocessed and processed feedstock can be between about 65.45 μm3 and about 47,712.94 μm3, corresponding to a desired particle size distribution of 5 to 45 microns for the processed powder. In some embodiments, an average or median aspect ratio, collectively, of preprocessed feedstock can be between 2:1 and 200:1, between 3:1 and 200:1, between 4:1 and 200:1, or between 5:1 and 200:1. However, any of the disclosed ratios/diameters can be used for the volume calculation. After processing, the particle size distribution in one example can be 5 to 45 microns. Other particle size distributions are also contemplated, including but not limited to particle size distributions of between 5 and 45 microns at a low end of the particle size distribution range and between 15 and 105 microns at a high end of the particle size distribution range (e.g., 5 to 15 microns, 15 to 45 microns, 45 to 105 microns).
In some embodiments, the volume distribution of the feedstock can be the same as the final spheroidized powder. In some embodiments, the overall volume of the feedstock can be the generally the same as the final spheroidized powder. In some embodiments, the overall volume of the feedstock can be within 1%, 2%, 3%, 4%, 5%, 10%, 15%, or 20% (or about 1%, about 2%, about 3%, about 4%, about 5%, about 10%, about 15%, or about 20%) of the final spheroidized powder.
In some embodiments, the feedstock may be generally spherical, or generally non-spherical. For example, the feedstock can be misshapen feedstock, cubes, filaments, wires, etc.
These aspect ratios are merely exemplary and other aspect ratios can be used as well.
Turnings from machining processes can be first collected, cleaned from the machining oils and other impurities, and then sieved to separate small particles/turnings that can directly be used as feedstock from larges ones that need further processing to reduce their size. An example method for further reducing the size of the turnings to the desired sizes is through milling. The product of this milling process is then sieved again into different sizes and the desired size is selected to be used as feedstock for spheroidization. The materials to be used can be selected from any subtractive process that uses metal and metal alloys stock to produce parts.
More specifically, in some embodiments, the scrap may be pre-processed before they are introduced into the plasma process. For example, the scrap may be sieved to remove large agglomerations and selected to the desired size to be processed in the plasma. In some embodiments, the scrap may be cleaned with water, surfactant, detergent, solvent or any other chemical such as acids to remove contamination. In some embodiments, the scrap may be magnetically cleaned if they are contaminated with any magnetic material. In some embodiments, the cleaning removes contaminants such as ceramics and oils. In some embodiments, the scrap can be pre-treated to de-oxidize it. In some embodiments, other elements or compounds can be added to compensate or modify the chemistry of the used parts. In some embodiments, the scrap can be de-dusted to remove fines. In some embodiments, no pre-processing may be performed. All of these pre-processing techniques can also be used on the post-milled scrap feedstock.
In some embodiments, the material to be milled can be titanium or titanium alloys. Specific titanium that can be used is commercially pure titanium (CpTi) (known as CpTi), TiAl, Ti-6Al-4V (Ti-6-4), and the particular titanium material/alloy does not limit the disclosure. Titanium can be particular problematic for milling as it is highly ductile, and thus would merely bend or change shape, and would not be broken down properly into a powder without embrittling, such as through hydrogenation or cryogenics. However, embodiments of the disclosure can mill titanium or titanium alloys without such an embrittling process. This can be done through the understanding and proper selection of the scrap material to be milled, such as by only choosing material having a particular volume/size/aspect ratio.
At block 106/108, the metal/alloy scraps can be sieved in order to sort between pieces that are too large and pieces that are small enough to be used as feedstock. If the pieces are small enough to be used as feedstock they can pass to block 112. If the pieces are too large, they can be milled at block 110 into smaller scrap metal/alloys in order to adjust particle size. In some embodiments, the milling can be jet milling, wet milling, and/or ball milling. Block 106 can be repeated in order to additionally sieve the milled scrap metal/alloys. Alternatively, it can be decided that the milled scrap metal/alloys are ready to be used as feedstock at block 112.
At block 112/114, the milled scrap metal/alloy that is ready to use as feedstock can be microwave plasma processed. Microwave plasma processing is described below and is also shown in
As discussed above, scrap material may be extremely complicated to prepare for a feedstock.
Dehydrogenated or Non-Hydrogenated Feed Material
One aspect of the present disclosure involves a process of spheroidization of metals and metal alloy using a microwave generated plasma. The process uses readily available existing pre-screened or non-prescreened raw materials made of metal and/or metal alloys as feedstock. The powder feedstock is entrained in inert and/or reducing and/or oxidizing gas environment and injected into the microwave plasma environment. Upon injection into a hot plasma, the feedstock is spheroidized and released into a chamber filled with an inert gas and directed into hermetically sealed drums where is it stored. This process can be carried out at atmospheric pressure, in a partial vacuum, or at a slightly higher pressure than atmospheric pressure. In alternative embodiments, the process can be carried out in a low, medium, or high vacuum environment. The process can run continuously and the drums are replaced as they fill up with spheroidized metal or metal alloy particles. Furthermore, provided the homogeneity of the microwave plasma process, particle agglomeration is also reduced, if not totally eliminated, thus leading to at least maintaining the particle size distribution of the original feed materials. However, it can be challenging to obtain the proper feedstock sizing because feedstock size criteria can be stringent. Different processing methods can be used to obtain different feedstock size criteria.
In some embodiments, a hydride-dehydride (HDH) process can be used to resize large metallic or metallic alloy pieces down to a finer particle size distribution through crushing, milling, and screening. Metal and alloy powders can be manufactured using the HDH process, where bulk feedstock, such as coarse metal powders or metal/metal alloy scraps, etc., are heated in a hydrogen-containing atmosphere at high temperature (˜700° C.) for a few days. This leads to the formation of a brittle metal hydride, which can readily be crushed into a fine power and sifted to yield a desired size distribution determined by the end user. To be useful in powdered metallurgy, hydrogen must be dissociated and removed from the metal by heating the metal hydride powder within vacuum for a period of time. The dehydrogenated powder must then be sifted to remove large particle agglomerations generated during process due to sintering. The typical resulting powder particles have an irregular or angular shape. The powder is submitted to a deoxidation process to remove any oxygen picked up by the powder during sifting and handling. Such HDH processes produce only coarse and irregular shaped particles. Such HDH processes must be followed by a spheroidization process, such as disclosed herein regarding a microwave plasma process, to make these particles spheroidal.
Embodiments of the disclosed HDH processes are primarily carried out as solid-state batch processes. A volume of metal powder can be loaded into a crucible(s) within a vacuum furnace. The furnace can be pumped down to a partial vacuum and is repeatedly purged with inert gas to eliminate the presence of undesired oxygen. Diffusion of the inert gas through the open space between the powder particles is slow making it difficult to fully eliminate oxygen, which otherwise contaminates the final product. Mechanical agitation may be used to churn powder allowing for more complete removal of oxygen.
Following oxygen purging the, hydrogenation may begin. The furnace is filled with hydrogen gas and heated up to a few days at high temperature to fully form the metal hydride. The brittle nature of the metal hydride allows the bulk material to be crushed into fine powders which are then screened into desired size distributions.
The next step is dehydrogenation. The screen hydride powder is loaded into the vacuum furnace then heated under partial vacuum, promoting dissociation of hydrogen from the metal hydride to form H2 gas and dehydrided metal. Dehydrogenation is rapid on the particle surface where H2 can readily leave the particles. However, within the bulk of the powder, H2 must diffuse through the bulk of the solid before it reaches surface and leave the particle. Diffusion through the bulk is a rate-limiting process “bottle-neck” requiring relatively long reaction time for complete dehydrogenation. The time and processing temperatures required for dehydrogenation are sufficient to cause sintering between particles, which results in the formation of large particle agglomerations in the final product. Post-process sifting can eliminate the agglomerations. Before the powder can be removed from the furnace, it can be sufficiently cooled to maintain safety and limit contamination. The thermal mass of the large furnaces may take minutes or hours to sufficiently cool. The cooled powders can then be spheroidized in a separate machine. In some embodiments, the feedstock may be a non-hydrogenated material. In some embodiments, the material hasn't undergone HDH but starts without any hydrogenation. In some embodiments, this can be carried out within the disclosed plasma process.
In some embodiments, the powder is entrained within an inert gas and injected into a microwave generated plasma environment (235) exhibiting a substantially uniform temperature profile between approximately 4,000 K and 8,000 K and under a partial vacuum. The hermetically sealed chamber process can also run at atmospheric pressure or slightly above atmospheric pressure to eliminate any possibility for atmospheric oxygen to leak into the process. The particles are melted in the plasma, spheroidized due to liquid surface tension, re-solidifying after exiting the plasma. The particles are then collected in sealed drums in an inert atmosphere. Within the plasma, the powder particles can be heated sufficiently to melt and cause convection of the liquid metal, causing dissociation of the hydrogen (if any remains after the HDH process) according to the reversible reaction where M=an arbitrary metal:
Within the partial vacuum, dissociation of hydrogen from the metal to form hydrogen gas is favored, driving the above reaction to the right. The rate of dissociation of hydrogen from the liquid metal is rapid, due to convection, which continually introduces H2 to the liquid surface where it can rapidly leave the particle.
As discussed above, feedstock sizing can be difficult to obtain. An HDH process can aid in the process of obtaining feedstock that meets certain size criteria.
Recycling Used Powder
Disclosed herein are embodiments of methods, devices, and assemblies for recycling/reusing/reconditioning used powders (e.g., waste byproducts), such as from post processing or yield loss. The previously used powders can be powders which have already undergone a manufacturing process, such as an additive manufacturing process. In some embodiments, the previously used powders were previously manufactured powders that are outside of the acceptable sizing of powders for particular processes, such as additive manufacturing. In particular, embodiments of the disclosure allow for the taking of used powder and converting it into a feedstock for a microwave plasma process to form a final spheroidized powder, which can then be used in different processes, such as additive manufacturing processes, metal injection molding (MIM), or hot isostatic Pressing (HIP) processes. This can be especially useful for powders that were manufactured using a gas atomized process, which can create excessively large particles. Thus, in some embodiments large and/or misshapen particles can be re-spheroidized. Used powder can be of differing quality and therefore it can be challenging to make use of used powder as feedstock. The feedstock can be contaminated or an incorrect size, or altogether difficult to process.
In some embodiments, the powders may be pre-processed before they are introduced into the plasma process. For example, the powders may be sieved to remove large agglomerations and selected the desired size to be processed in the plasma. In some embodiments, the powders may be cleaned with water, surfactant, detergent, solvent or any other chemical such as acids to remove contamination. In some embodiments, the powders may be magnetically cleaned if they are contaminated with any magnetic material. In some embodiments, the powder can be pre-treated to de-oxidize it. In some embodiments, other elements or compounds can be added to compensate or modify the chemistry of the powder. In some embodiments, the powder can be de-dusted to remove fines. In some embodiments, no pre-processing may be performed.
In some embodiments, the previously used powder can be modified to make it more applicable as the feedstock as the previous processing can make the powder/particles unusable. In some embodiments, “satellites”, which can hurt/reduce flow can be removed. Further, used powder can become agglomerated, and the disclosed process can separate the particles in the powder. In some embodiments, contaminants, such as organics, can be removed. In some embodiments, carbon, nitrogen, oxygen, and hydrogen can be removed from the previously used powder by the disclosed process. In some embodiments, artifacts can be removed. The disclosed process can also improve the flowability of the used powders. In some embodiments, surface texture can be adjusted to reduce surface roughness of used powder to improve flowability. In some embodiments, flowability can be improved by absorbing satellites. In some embodiments, residence time and power levels can be modified to absorb satellites or evaporate them, such as with minimal affect the chemistry of the bulk powders.
Generally, embodiments of the disclosed methods can make the used powered spherical again, for example a powder having particles that were spherical and have become not spherical during a previous process. These previous processes can include, but are not limited to, gas atomization, laser bed fusion, electron-beam melting, and binder jetting. In some embodiments, the used powder can be larger powder waste from an electron beam process, which can then be made into a smaller powder for laser application. In some embodiments, the used powder can be larger powder waste from a gas atomization process, which can then be made into a smaller powder for laser application. In some embodiments, after use, the powder has agglomerations, increased oxygen content that is out of specification, contamination from soot and inorganic materials, and/or deformation which makes them non-spherical. In these embodiments, the powders cannot be reused without processing.
In some embodiments, PSD is with a minimum diameter of 1 micrometers (μm) and a maximum diameter of 22 μm, or a minimum of 5 μm and a maximum of 15 μm, or a minimum of 15 μm and a maximum of 45 μm or a minimum of 22 μm and a maximum of 44 μm, or a minimum of 20 μm to a maximum of 63 μm, or a minimum of 44 μm and a maximum of 70 μm, or a minimum of 70 μm and a maximum of 106 μm, or a minimum of 105 μm to a maximum of 150 μm, or a minimum of 106 μm and a maximum of 300 μm. As will be appreciated, these upper and lower values are provided for illustrative purposes only, and alternative PSD values may be used in other embodiments. In some embodiments, the disclosed processing methods retains alloy elements especially highly volatile elements such as Al, Mg, Ti, and Cu from the used powder.
This disclosure describes the rejuvenation of used powders described above to produce fresh powders with improved specifications. The microwave plasma process that is made of a microwave generated plasma is used to rejuvenate used powders described above to better specifications, so they can be used again as feedstock to the powder metallurgy processes described above.
In some embodiments, through the processing of used powders, the particle size distribution can be maintained. In some embodiments, the particle size distribution can be improved/tightened by absorbing satellites. In some embodiments, the particle size distribution can be improved/tightened by re-spheroidizing large agglomerates. For example, for laser powder bed with 15-45 micron particle size distribution, used powder can include a) 5% by weight of satellites that are absorbed or evaporated by the microwave plasma process, and b) large misshapen agglomerations, both of which can be removed by embodiments of the disclosed process. As an example, powders having a particle size distribution of 45-106 micron can be reduced to 15-45 micron, such as for laser powder bed. In some embodiments, the particle size distribution can be the D50 of the particles in the powder.
In some embodiments, through the processing of used powders, the particle size diameter can be altered. In some embodiments, the particle size diameter can be reduced. In some embodiments, the particle size diameter can be reduced to produce smaller diameter particle size by partially vaporizing the surface of large particles. For example, powder from an e-beam powder bed with 45-106 micron particle size diameter can be used to produce powder with 15-45 micron particle size to be used in a laser bed additive manufacturing process.
As shown in the figures, the methods disclosed herein can greatly tighten the particle size distribution, while also reducing the overall size of the powders. For example, the 50th percentile of particles is around 34 microns, whereas the powder originally had a 50th percentile of particles of 52 microns. Thus, the average particle size can be reduced (or increased if needed in other embodiments). Further, the overall powder distribution has been narrowed, where the original particles spanned from 21-101 microns (from 10% to 95%), whereas after processing the particles span from 23 to 58 microns (from 10% to 95%).
In some embodiments, the 50 percentile of particle sizes can be reduced by 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the 50 percentile of particle sizes can be reduced by greater than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the 50 percentile of particle sizes can be reduced by less than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%).
In some embodiments, the particle size distribution from 10% to 95% can be reduced by 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the particle size distribution from 10% to 95% can be reduced by greater than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the particle size distribution from 10% to 95% can be reduced by less than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%).
In some embodiments, previously used powders, such as through gas atomization, can produce powders that are too small for use in manufacturing processes, such as additive manufacturing process. Therefore, embodiments of the disclosure can be used to increase the overall size of the particles. For example, in some embodiments, the 50 percentile of particle sizes can be increased by 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the 50 percentile of particle sizes can be increased by greater than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%). In some embodiments, the 50 percentile of particle sizes can be increased by less than 10, 20, 30, 40, 50, 60, or 70% (or about 10, about 20, about 30, about 40, about 50, about 60, or about 70%).
The plasma gases can be specific to the materials of the powders. As an example, in the case of metal and metal alloys that do not readily form nitrides, nitrogen gas can be used. One example is the processing of Inconel 718 where when it is run in a nitrogen plasma environment, the processed powder is not chemically altered and do not present any nitrogen incorporation into the bulk powder.
In the case of metals and metal alloys that readily react with nitrogen, noble gases such as argon, argon/helium mixture can be used. Also these noble gases can be mixed with hydrogen gas to increase the uniformity of the plasma. An example of a metal alloy that is susceptible to reaction with nitrogen is titanium alloy Ti 6% Al-4% V (by weight).
In some instances, noble gases and mixtures such as argon a and argon/hydrogen mixtures are used to avoid any reaction between the powders and the plasma gases. In other instances, nitrogen can be used when the processed powder is not reactive with the above mentioned gas.
The reconditioning of the used powder/particles can include the removal of artifacts, such as from a laser sintering process. Further, satellites and agglomerated materials due to overheating, for example from a laser process outside a build line, can be removed. The particular process to form the used particles, such as additive processes, powder bed fusion, and binder jetting, is not limiting and other processes could have been performed on the original particles.
The reconditioning of the used powder/particles can allow the powder/particles to, in some embodiments, regain their original rheological properties (such as bulk density, flowability, etc.). In fact, in some embodiments, the reconditioning of used powder/particles can also improve the rheological properties. This can be achieved through the removing of any satellite on the surface through surface melting of the satellites and their incorporation into the bulk of the particle. In some cases, full melting of the particles will densify particles and remove any porosity. Full melting of the particles can be achieved through higher powder density of the plasma and longer residence time. Also the fact of spheroidizing the powders increases their flowability. Angular shaped powders are very hard to flow and their flowability increases as their shape becomes more spherical.
A satellite can be a main powder particle that has a size that is within the defined particle size distribution to which a small particle of much smaller diameter that is outside the particle size distribution than the diameter of the main particle is agglomerated either through sintering or other physical processes.
An agglomeration can be two or more particles which coalesce to form a larger particle.
Further, the reconditioning can minimize oxygen pickup during the reconditioning. This can be achieved by, for example, adding hydrogen or reducing agent, running in a close environment, or running at a high temperature. In some embodiments, atmospheric pressure inert gas can be used. In some embodiments, a low oxygen environment can be used.
In some embodiments, the alloying component chemistry or minor component chemistry may not be altered. In some embodiments, certain elements with low melting temperatures can be removed from the powder.
In some embodiments, the previously used powder particles can be metal or metal alloys. In some embodiments, the previously used powder particles can be titanium or titanium alloys. Specific titanium that can be used is Ti (known as CpTi), TiAl, Ti-6-4, and the particular titanium material/alloy does not limit the disclosure. Other materials can be used as well, for example other ductile materials. In some embodiments, nickel and nickel alloys, cobalt, and cobalt alloys, steel, or stainless steel can be the previously used powder particles and the particular material is not limiting. In some embodiments, nickel metals/alloys, such as Inconel 718 and 625 superalloys, can be used. In some embodiments, YSZ, MY, CoO, Al2O3—TiO2, Stainless 316L, and 17-4 can be used.
As discussed above, used powder may be extremely complicated to prepare for a feedstock.
Sphericity
In some embodiments, the final particles achieved by the plasma processing can be spherical or spheroidal, terms which can be used interchangeably. Advantageously, by using the critical and specific disclosure relevant to each of the different feedstocks disclosed, all of the feedstocks can be transformed into the spherical powders.
Embodiments of the present disclosure are directed to producing particles that are substantially spherical or spheroidal or have undergone significant spheroidization. In some embodiments, spherical, spheroidal or spheroidized particles refer to particles having a sphericity greater than a certain threshold. Particle sphericity can be calculated by calculating the surface area of a sphere As,ideal with a volume matching that of the particle, V using the following equation:
and then comparing that idealized surface area with the measured surface area of the particle,
In some embodiments, particles can have a sphericity of greater than 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 0.91, 0.95, or 0.99 (or greater than about 0.5, about 0.6, about 0.7, about 0.75, about 0.8, about 0.9, about 0.91, about 0.95, or about 0.99). In some embodiments, particles can have a sphericity of 0.75 or greater or 0.91 or greater (or about 0.75 or greater or about 0.91 or greater). In some embodiments, particles can have a sphericity of less than 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 0.91, 0.95, or 0.99 (or less than about 0.5, about 0.6, about 0.7, about 0.75, about 0.8, about 0.9, about 0.91, about 0.95, or about 0.99). In some embodiments, a particle is considered to be spherical, spheroidal or spheroidized if it has a sphericity at or above any of the aforementioned sphericity values, and in some preferred embodiments, a particle is considered to be spherical if its sphericity is at or about 0.75 or greater or at or about 0.91 or greater.
In some embodiments, a median sphericity of all particles within a given powder can be greater than 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 0.91, 0.95, or 0.99 (or greater than about 0.5, about 0.6, about 0.7, about 0.75, about 0.8, about 0.9, about 0.91, about 0.95, or about 0.99). In some embodiments, a median sphericity of all particles within a given powder can be less than 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 0.91, 0.95, or 0.99 (or less than about 0.5, about 0.6, about 0.7, about 0.75, about 0.8, about 0.9, about 0.91, about 0.95, or about 0.99). In some embodiments, a powder is considered to be spheroidized if all or a threshold percentage (as described by any of the fractions below) of the particles measured for the given powder have a median sphericity greater than or equal to any of the aforementioned sphericity values, and in some preferred embodiments, a powder is considered to be spheroidized if all or a threshold percentage of the particles have a median sphericity at or about 0.75 or greater or at or about 0.91 or greater.
In some embodiments, the fraction of particles within a powder that can be above a given sphericity threshold, such as described above, can be greater than 50%, 60%, 70%, 80%, 90%, 95%, or 99% (or greater than about 50%, about 60%, about 70%, about 80%, about 90%, about 95%, or about 99%). In some embodiments, the fraction of particles within a powder that can be above a given sphericity threshold, such as described above, can be less than 50%, 60%, 70%, 80%, 90%, 95%, or 99% (or less than about 50%, about 60%, about 70%, about 80%, about 90%, about 95%, or about 99%).
Particle size distribution and sphericity may be determined by any suitable known technique such as by SEM, optical microscopy, dynamic light scattering, laser diffraction, manual measurement of dimensions using an image analysis software, for example from about 15-30 measures per image over at least three images of the same material section or sample, and any other techniques.
In some embodiments, only problematic particles (“bad particles”) are used in the disclosed process. For example, the problematic particles can be separated from particles that could be used as a feedstock for the microwave plasma process without any further processing (“good particles”). In some embodiments, both the good and the bad particles can be put into the process.
Powder metallurgy processes such as additive manufacturing, thermal and cold spray coating produce a large amount of waste powders. In some instances, those powders' morphology is changed from the original fresh powders and can include satellites, partial melting and/or other contaminants. Those changes can lead to a deterioration of the powder flowability, tap and bulk density, and sometime contamination such as carbon and nitrogen, and render the used powders useless for the same processes. Recycling those used powders to their original specifications can provide an economical advantage and lower costs.
In some embodiments that involve used parts, the used parts may be pre-processed before they are introduced into the plasma process. For example, the used parts may be sieved to remove large agglomerations and selected to the desired size to be processed in the plasma. In some embodiments, the used parts may be cleaned with water, surfactant, detergent, solvent or any other chemical such as acids to remove contamination. In some embodiments, the used parts may be magnetically cleaned if they are contaminated with any magnetic material. In some embodiments, the used parts can be pre-treated to de-oxidize it. In some embodiments, other elements or compounds can be added to compensate or modify the chemistry of the used parts. In some embodiments, the used parts can be de-dusted to remove fines. In some embodiments, no pre-processing may be performed. All of these pre-processing techniques can also be used on the post-milled powder.
In some embodiments where the material is milled, the material to be milled can be titanium or titanium alloys. Specific titanium that can be used is Ti (known as CpTi), TiAl, Ti-6-4, and the particular titanium material/alloy does not limit the disclosure. Titanium can be particular problematic for milling as it is highly ductile, and thus would merely bend or change shape, and would not be broken down properly into a powder without embrittling, such as through hydrogenation or cryogenics. However, embodiments of the disclosure can mill titanium or titanium alloys without such an embrittling process. This can be done through the understanding and proper selection of the scrap material to be milled, such as by only choosing material having a particular volume/size/aspect ratio.
Other materials can be used as well, for example other ductile materials. In some embodiments, nickel and nickel alloys, steel, stainless steel, copper, copper alloys, and Hastealloy can be used and the particular material is not limiting. In some embodiments, nickel metals/alloys, such as Inconel 718 and 625 superalloys, can be used. In some embodiments, oxygen content of the material needs to be in the range of a few ppm to about 2% in the case of reactive materials and a few ppm to about 1% for non-reactive materials.
In some embodiments where the material is milled, the materials can come into the milling procedure having particular advantageous properties, such as a work-hardened microstructure. Embodiments of the disclosure allow for the work-hardened microstructure to last all the way through the microwave plasma processing, thereby forming a final spheroidized powder product retaining the work-hardened material. This can be done by only microwave plasma processing the outer surface of the particles, thereby retaining the internal work-hardened microstructure. However, in some embodiments the microwave plasma processing heats/melts the particles all the way through to change the microstructure from what it originally was.
A Scherrer Equation can be used to calculate grain sizes using a full width half maximum (FWHM). This can show how at least a partial retention of microstructure is achieved from the original microstructure of the feedstock to the post plasma processing microstructure for any of the above processes, such as the recycling of gas atomized powders, the recycling of used powders, or the grave-to-cradle process. The equation can be as shown:
where B: Peak Width in radians at particular 2Θ, Θ: Bragg angle, K:Scherrer Constant, value between 0.62 to 2.08, λ: Wavelength of the x-ray used, and L: Average crystallite size. An example is as follows:
Thus, work hardened (or other microstructure) metals and metal alloys feedstock can be spheroidized without affecting the microstructure by a high heating rate that will only melt the surface of the particles without affecting the bulk, hence preserving the microstructure. The feedstock materials can be turnings that have been hardened during the machining process, or large scrap pieces made of hardened material and that is milled to the desired size to be used as feedstock for the spheroidization process.
In some embodiments where the material is milled, a miller can determine the thickness of materials that can be milled based on the prescribed desired volume.
Accordingly, in some embodiments of the disclosure a user can perform the selection of pieces of ductile material that can be milled to a desired volume without embrittling the material, and then milling the material without having to embrittle first to produce particles each having the desired volume as feed material for the microwave plasma torch. The user can then introduce the particles into the plasma torch and process the powder to retain work hardened microstructure while it spheroidal.
In some embodiments that involve scrap materials, scrap material made of ductile metals and/or metal alloys is milled in a process to avoid the material hardening. The ductile product of the milling process is then sieved to different size distributions to be used as feedstock for spheroidization in the microwave plasma melting process. To preserve the ductility of the feedstock particles, the heating and cooling rates can be controlled through the residence time of the particles in the plasma and in the plasma afterglow.
Embodiments of the disclosed process can include feeding the powders using a powder feeder into a microwave generated plasma where the power density, gas flows and residence time are controlled. The process parameters such as power density, flow rates and residence time of the powder in the plasma can depend on the powder material's physical characteristics, such as the melting point and thermal conductivity. The power density can range from 20 W/cm3 to 500 W/cm3 (or about 20 W/cm3 to about 500 W/cm3). The total gas flows can range from 0.1 cfm to 50 cfm (or about 0.1 cfm to about 50 cfm), and the residence time can be tuned from 1 ms to 10 sec (or about 1 ms to about 10 sec). This range of process parameters will cover the required processing parameters for materials with a wide range of melting point and thermal conductivity.
In some embodiments that involve scrap materials, the scrap material can be material that is direct from the factory floor. In some embodiments, any remaining contaminants, such as oils, grease, or other material, can be removed before or during the disclosed process (either prior to milling, during milling, or during the microwave plasma melting).
In some embodiments, the ability to control oxygen can provide advantages, for example in the case of titanium scrap.
In some embodiments where the material is milled, the milling can be done in water. Thus, as the titanium is sheared apart fresh titanium surfaces oxidize, which increases the oxygen level.
Different environmental gasses can be used for different applications. As an example, in the case of metal and metal alloys that do not readily form nitrides, nitrogen gas can be used. One example is the processing of Inconel 718 where when it is run in a nitrogen plasma environment, the processed powder is not chemically altered and do not present any nitrogen incorporation into the bulk powder.
In some embodiments, the feedstock could be of various morphology such as angular powder, angular chips, irregular powder, and sponge powders. The feedstock can be processed to meet certain criteria for size, gas content, purity contamination and chemistry by processing such as but not limited to grinding, milling, cleaning, washing, drying and screening. The cleaning includes removing organic, ceramic, or other metallic contaminants.
In some embodiments, nickel or nickel alloys, steel or steel alloys, cobalt or cobalt alloys, and titanium or titanium alloys can be used in embodiments of the disclosure, and the particular material is not limiting. In some embodiments, ceramics can be used.
In the case of metals and metal alloys that readily react with nitrogen, noble gases such as argon, argon/helium mixture can be used. Also these noble gases can be mixed with hydrogen gas to increase the uniformity of the plasma. An example of a metal alloy that is susceptible to reaction with nitrogen is titanium alloy Ti 6% Al-4% V (by weight).
Microwave Plasma Processing
The process parameters can be optimized to obtain maximum spheroidization depending on the feedstock initial condition. For each feedstock characteristic, process parameters can be optimized for a particular outcome. U.S. Pat. Pub. No. 2018/0297122, U.S. Pat. No. 8,748,785 B2, and U.S. Pat. No. 9,932,673 B2 disclose certain processing techniques that can be used in the disclosed process, specifically for microwave plasma processing. Accordingly, U.S. Pat. Pub. No. 2018/0297122, U.S. Pat. No. 8,748,785 B2, and U.S. Pat. No. 9,932,673 B2 are incorporated by reference in its entirety and the techniques describes should be considered to be applicable to the feedstock described herein.
One aspect of the present disclosure involves a process of spheroidization of metals and metal alloys using a microwave generated plasma. The powder feedstock is entrained in an inert and/or reducing gas environment and injected into the microwave plasma environment. Upon injection into a hot plasma (or plasma plume or exhaust), the feedstock is spheroidized and released into a chamber filled with an inert gas and directed into hermetically sealed drums where is it stored. This process can be carried out at atmospheric pressure, in a partial vacuum, or at a slightly higher pressure than atmospheric pressure. In alternative embodiments, the process can be carried out in a low, medium, or high vacuum environment. The process can run continuously and the drums are replaced as they fill up with spheroidized metal or metal alloy particles.
The rate of cooling of the spheroidized metal and metal alloys can be controlled to strategically influence the microstructure of the powder. For example, rapid cooling of α-phase titanium alloys facilitates an acicular (martensite) structure. Moderate cooling rates produce a Widmanstätten microstructure, and slow cooling rates form an equiaxed microstructure. By controlling the process parameters such as cooling gas flow rate, residence time, cooling gas composition etc., microstructure of the metal and metal alloys can be controlled. The precise cooling rates required to form these structures is largely a function of the type and quantity of the alloying elements within the material.
The rate of cooling, especially when combined with the consistent and uniform heating capabilities of a microwave plasma plume, allow for control over the final microstructure. As a result, the above methods can be applied to processing metal (e.g., titanium and titanium alloys such as Ti 6-4) feedstock. For example, while certain methods may use a metal hydride feedstock, the control over microstructure is not limited thereto. In particular, the method and powders created by the present technology include the use of non-hydrided sources. For example, titanium metal and various titanium metal alloys can be utilized as the feedstock source. These materials can be crushed or milled to create particles for treatment within a microwave plasma torch.
Cooling processing parameters include, but are not limited to, cooling gas flow rate, residence time of the spheroidized particles in the hot zone, and the composition or make of the cooling gas. For example, the cooling rate or quenching rate of the particles can be increased by increasing the rate of flow of the cooling gas. The faster the cooling gas is flowed past the spheroidized particles exiting the plasma, the higher the quenching rate-thereby allowing certain desired microstructures to be locked-in. Residence time of the particles within the hot zone of the plasma can also be adjusted to provide control over the resulting microstructure. That is, the length of time the particles are exposed to the plasma determines the extent of melting of the particle (i.e., surface of the particle melted as compared to the inner most portion or core of the particle). Consequently, the extent of melting effects the extent of cooling needed for solidification and thus it is a cooling process parameter. Microstructural changes can be incorporated throughout the entire particle or just a portion thereof depending upon the extent of particle melting. Residence time can be adjusted by adjusting such operating variables of particle injection rate and flow rate (and conditions, such as laminar flow or turbulent flow) within the hot zone. Equipment changes can also be used to adjust residence time. For example, residence time can be adjusted by changing the cross-sectional area of the hot zone.
Another cooling processing parameter that can be varied or controlled is the composition of the cooling gas. Certain cooling gases are more thermally conductive than others. For example helium is considered to be a highly thermally conductive gas. The higher the thermal conductivity of the cooling gas, the faster the spheroidized particles can be cooled/quenched. By controlling the composition of the cooling gas (e.g., controlling the quantity or ratio of high thermally conductive gasses to lesser thermally conductive gases) the cooling rate can be controlled.
As is known in metallurgy, the microstructure of a metal is determined by the composition of the metal and heating and cooling/quenching of the material. In the present technology, by selecting (or knowing) the composition of the feedstock material, and then exposing the feedstock to a plasm that has the uniform temperature profile and control there over as provided by the microwave plasma torch, followed by selecting and controlling the cooling parameters control over the microstructure of the spheroidized metallic particle is achieved. In addition, the phase of the metallic material depends upon the compositions of the feed stock material (e.g., purity, composition of alloying elements, etc.) as well thermal processing. Titanium has two distinct phases known as the alpha phase (which has a hexagonal close packed crystal structure) and a beta phase which has a body centered cubic structure. Titanium can also have a mixed α+β phase. The different crystal structures yield different mechanical responses. Because titanium is allotropic it can be heat treated to yield specific contents of alpha and beta phases. The desired microstructure is not only a description of the grains (e.g., martensitic vs. equiaxed) but also the amount and location of different phases throughout.
In one exemplary embodiment, inert gas is continually purged surrounding a powdered metal feed to remove oxygen within a powder-feed hopper. A continuous volume of powder feed is then entrained within an inert gas and fed into the microwave generated plasma for dehydrogenation or for composition/maintaining purity of the spheroidized particles. In one example, the microwave generated plasma may be generated using a microwave plasma torch, as described in U.S. Patent Publication No. US 2013/0270261, and/or U.S. Pat. Nos. 8,748,785, 9,023,259, 9,259,785, and 9,206,085, each of which is hereby incorporated by reference in its entirety. In some embodiments, the particles are exposed to a uniform temperature profile at between 4,000 and 8,000 K within the microwave generated plasma. In some embodiments, the particles are exposed to a uniform temperature profile at between 3,000 and 8,000 K within the microwave generated plasma. Within the plasma torch, the powder particles are rapidly heated and melted. Liquid convection accelerates H2 diffusion throughout the melted particle, continuously bringing hydrogen (H2) to the surface of the liquid metal hydride where it leaves the particle, reducing the time each particle is required to be within the process environment relative to solid-state processes. As the particles within the process are entrained within an inert gas, such as argon, generally contact between particles is minimal, greatly reducing the occurrence of particle agglomeration. The need for post-process sifting is thus greatly reduced or eliminated, and the resulting particle size distribution could be practically the same as the particle size distribution of the input feed materials. In exemplary embodiments, the particle size distribution of the feed materials is maintained in the end products.
Within the plasma, plasma plume, or exhaust, the melted metals are inherently spheroidized due to liquid surface tension. As the microwave generated plasma exhibits a substantially uniform temperature profile, more than 90% spheroidization of particles could be achieved (e.g., 91%, 93%, 95%, 97%, 99%, 100%). After exiting the plasma, the particles are cooled before entering collection bins. When the collection bins fill, they can be removed and replaced with an empty bin as needed without stopping the process.
In one exemplary embodiment, inert gas is continually purged surrounding a powdered metal feed to remove oxygen within a powder-feed hopper. A continuous volume of powder feed is then entrained within an inert gas and fed into the microwave generated plasma for composition/maintaining purity of the spheroidized particles. In one example, the microwave generated plasma may be generated using a microwave plasma torch, as described in U.S. Patent Publication No. US 2013/0270261, and/or U.S. Pat. No. 8,748,785, each of which is hereby incorporated by reference in its entirety. In some embodiments, the particles are exposed to a uniform temperature profile at between 4,000 and 8,000 K within the microwave generated plasma. Within the plasma torch, the powder particles are rapidly heated and melted. As the particles within the process are entrained within an inert gas, such as argon, generally contact between particles is minimal, greatly reducing the occurrence of particle agglomeration. The need for post-process sifting is thus greatly reduced or eliminated, and the resulting particle size distribution could be practically the same as the particle size distribution of the input feed materials. In exemplary embodiments, the particle size distribution of the feed materials is maintained in the end products.
Within the plasma, the melted metals are inherently spheroidized due to liquid surface tension. As the microwave generated plasma exhibits a substantially uniform temperature profile, more than 90% spheroidization of particles could be achieved (e.g., 91%, 93%, 95%, 97%, 99%, 100%). In embodiments, both spheroidization and tailoring (e.g., changing, manipulating, controlling) microstructure are addressed or, in some instances, partially controlled, by treating with the microwave generated plasma. After exiting the plasma, the particles are cooled before entering collection bins. When the collection bins fill, they can be removed and replaced with an empty bin as needed without stopping the process.
As discussed above, the plasma torch can be a microwave generated plasma or an RF plasma torch. In one example embodiment, an AT-1200 rotating powder feeder (available from Thermach Inc.) allows a good control of the feed rate of the powder. In an alternative embodiment, the powder can be fed into the plasma using other suitable means, such as a fluidized bed feeder. The feed materials may be introduced at a constant rate, and the rate may be adjusted such that particles do not agglomerate during subsequent processing steps. In another exemplary embodiment, the feed materials to be processed are first sifted and classified according to their diameters, with a minimum diameter of 1 micrometers (μm) and a maximum diameter of 22 μm, or a minimum of 5 μm and a maximum of 15 μm, or a minimum of 15 μm and a maximum of 45 μm or a minimum of 22 μm and a maximum of 44 μm, or a minimum of 20 μm to a maximum of 63 μm, or a minimum of 44 μm and a maximum of 70 μm, or a minimum of 70 μm and a maximum of 106 μm, or a minimum of 105 μm to a maximum of 150 μm, or a minimum of 106 μm and a maximum of 300 μm. As will be appreciated, these upper and lower values are provided for illustrative purposes only, and alternative size distribution values may be used in other embodiments. This eliminates recirculation of light particles above the hot zone of the plasma and also ensures that the process energy present in the plasma is sufficient to melt the particles without vaporization. Pre-screening allows efficient allocation of microwave power necessary to melt the particles without vaporizing material.
In some embodiments, the environment and/or sealing requirements of the bins are carefully controlled. That is, to prevent contamination or potential oxidation of the powders, the environment and/or seals of the bins are tailored to the application. In one embodiment, the bins are under a vacuum. In one embodiment, the bins are hermetically sealed after being filled with powder generated in accordance with the present technology. In one embodiment, the bins are back filled with an inert gas, such as, for example argon. Because of the continuous nature of the process, once a bin is filled, it can be removed and replaced with an empty bin as needed without stopping the plasma process.
The methods and processes in accordance with the disclosure can be used to make spherical metal powders or spherical metal alloy powders. For example, if the starting feed material is a titanium material, the resulting powder will be a spherical titanium powder. If the starting feed material is a titanium alloy material, the resulting powder will be a spherical titanium alloy powder. In one embodiment that features the use of a starting titanium alloy material, the resulting spherical titanium alloy powder comprises spherioidized particles of Ti Al6-V4, with between 4% to 7% weight aluminum (e.g., 5.5 to 6.5% Al) (or about 4% to about 7%, or about 5.5% to about 6.5%) and 3% to 5% weight vanadium (e.g., 3.5 to 4.5% vanadium) (or about 3% to about 5%, or about 3.5 to about 4.5%). In some embodiments, the material may have a composition that is within 10% (+/−10%) of the wt. % listed in this paragraph. In some embodiments, the feed material may be Ti Al6-V4 (or Ti-6-4) and wherein the melting and spheroidizing is controlled such that the spheroidized powder comprises Ti Al6-V4 as discussed herein. E.g., in some embodiments both the initial feedstock and the final powder is Ti Al6-V4. In some embodiments, the starting feedstock and final powder can have a different composition, but still be within the Ti Al6-V4 discussed herein. In some embodiments, the starting feedstock and final powder can have a different composition.
In some embodiments, the processing discussed herein, such as the microwave plasma processing, can be controlled to prevent and/or minimize aluminum for escaping the feedstock during the melt, which can maintain the desired composition/microstructure.
Generally, the downstream spheroidization method can utilize two main hardware configurations to establish a stable plasma plume which are: annular torches, such as described in U.S. Pat. Pub. No. 2018/0297122, or swirl torches described in U.S. Pat. No. 8,748,785 B2 and U.S. Pat. No. 9,932,673 B2. Both
The metal feed materials 314 can be introduced into a microwave plasma torch 302. A hopper 306 can be used to store the metal feed material 314 before feeding the metal feed material 314 into the microwave plasma torch 302, plume, or exhaust. The feed material 314 can be injected at any angle to the longitudinal direction of the plasma torch 302. 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, or 55 degrees. In some embodiments, the feedstock can be injected an angle of greater than 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, or 55 degrees. In some embodiments, the feedstock can be injected an angle of less than 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, or 55 degrees. In alternative embodiments, the feedstock can be injected along the longitudinal axis of the plasma torch. The microwave radiation can be brought into the plasma torch through a waveguide 304. The feed material 314 is fed into a plasma chamber 310 and is placed into contact with the plasma generated by the plasma torch 302. When in contact with the plasma, plasma plume, or plasma exhaust, the feed material melts. While still in the plasma chamber 310, the feed material 314 cools and solidifies before being collected into a container 312. Alternatively, the feed material 314 can exit the plasma chamber 310 while still in a melted phase and cool and solidify outside the plasma chamber. In some embodiments, a quenching chamber may be used, which may or may not use positive pressure. While described separately from
In some embodiments, implementation of the downstream injection method may use a downstream swirl, extended spheroidization, or quenching. A downstream swirl refers to an additional swirl component that can be introduced downstream from the plasma torch to keep the powder from the walls of the tube. An extended spheroidization refers to an extended plasma chamber to give the powder longer residence time. In some implementations, it may not use a downstream swirl, extended spheroidization, or quenching. In some embodiments, it may use one of a downstream swirl, extended spheroidization, or quenching. In some embodiments, it may use two of a downstream swirl, extended spheroidization, or quenching.
Injection of powder from below may results in the reduction or elimination of plasma-tube coating in the microwave region. When the coating becomes too substantial, the microwave energy is shielded from entering the plasma hot zone and the plasma coupling is reduced. At times, the plasma may even extinguish and become unstable. Decrease of plasma intensity means decreases in spheroidization level of the powder. Thus, by feeding feedstock below the microwave region and engaging the plasma plume at the exit of the plasma torch, coating in this region is eliminated and the microwave powder to plasma coupling remains constant through the process allowing adequate spheroidization.
Thus, advantageously the downstream approach may allow for the method to run for long durations as the coating issue is reduced. Further, the downstream approach allows for the ability to inject more powder as there is no need to minimize coating.
The desired microstructure of the spheroidized particle (end product) can be tailored to meet the demands and material characteristics of its use. For example, the desired microstructure may be one that provides improved ductility (generally associated with the α-phase). In another example, the desired microstructure may be associated with the inclusion of α+β phase or regions of α with islands of β phase or vice-versa. Without wishing to be bound by theory, it is believe that the methods of the present disclosure allow for control over the phase of the spheroidized particles as the microwave generated plasma has a uniform temperature profile, fine control over the hot zone, and the ability to select and adjust cooling processing parameters.
Using the methods of the present technology, various microstructures, crystal structures and regions of differing microstructure and/or crystal structures can be produced. Accordingly, new spheroidal titanium particles can be produced efficiently. For example, due to the abilities to control the hot zone and cooling processing parameters, the present technology allows an operator to create multiple regions within the spheroidal particle.
In another embodiment, not shown, the entire feed stock particle can be melted and cooling parameters can be selected and applied to create a crystal structure that has the same phase as the feed stock material (e.g., retains α-phase) or is transformed to a new phase or mixture of phases. Similarly, cooling processing parameters can be selected and applied to create spheroidal particles that have the same microstructure throughout the particle or various microstructures in two or more regions (e.g., shell region, core region).
Certain embodiments of the disclosure are encompassed in the claims presented at the end of this specification, or in other claims presented at a later date. Additional embodiments are encompassed in the following set of numbered embodiments:
Embodiment 1. A method for manufacturing a spheroidized powder from scrap metal or used metal parts, the method comprising:
Embodiment 2. The method of Embodiment 1, wherein the milled or crushed particles have a desired particle size distribution.
Embodiment 3. The method of Embodiment 2, wherein the desired particle size distribution is 15 to 63 microns.
Embodiment 4. The method of Embodiment 1, wherein the milled or crushed particles have a desired range of particle volumes.
Embodiment 5. The method of any of the preceding embodiments, wherein the particles are milled or crushed without embrittling the scrap metal or used metal parts.
Embodiment 6. The method of any of the preceding embodiments, further comprising milling or crushing the scrap metal or used metal parts to produce the metallic particles.
Embodiment 7. The method of any of the preceding embodiments, wherein the scrap metal or used metal parts comprise titanium or titanium alloy.
Embodiment 8. The method of any one of Embodiments 1-7, wherein the scrap metal or used metal parts comprise nickel or nickel alloy.
Embodiment 9. The method of any one of Embodiments 1-7, wherein the scrap metal or used metal parts comprise cobalt or cobalt alloy.
Embodiment 10. The method of any one of Embodiments 1-7, wherein the scrap metal or used metal parts comprise steel or steel alloy.
Embodiment 11. The method of any one of Embodiments 1-7, wherein the scrap metal or used metal parts comprise a ductile metal or metal alloy.
Embodiment 12. The method of any of the preceding embodiments, wherein the metallic particles comprise milled turnings resulting from subtractive manufacturing.
Embodiment 13. The method of any one of Embodiments 1-11, wherein the scrap metal or used metal parts comprise sharp turnings, saw swarfs, grinding swarfs, grinding fines, and/or wash line fines.
Embodiment 14. The method of any of the preceding embodiments, wherein the metallic particles comprise a work hardened microstructure that is at least partially retained after the melting and spheroidizing.
Embodiment 15. The method of any of the preceding embodiments, wherein the metallic particles are only partially surface melted.
Embodiment 16. A method for manufacturing a spheroidized powder from scrap metal or used metal parts, the method comprising:
applying the microwave plasma process to the metallic particles within the determined range of particle volumes to form spheroidized powder.
Embodiment 17. The method of Embodiment 16, further comprising selecting portions of the scrap metal or used metal parts having a size and/or aspect ratio suitable for milling to the determined range of particle volumes.
Embodiment 18. The method of Embodiment 16 or 17, wherein the determined range of particle volumes is between 15 and 63 microns.
Embodiment 19. The method of any one of Embodiments 16-18, wherein the scrap metal or used metal parts comprise a work hardened microstructure that is retained in the spheroidized powder after applying the microwave plasma process.
Embodiment 20. The method of any one of Embodiments 16-19, wherein the milling is performed in water.
Embodiment 21. The method of any one of Embodiments 16-20, further comprising processing the spheroidized powder in an additive manufacturing process.
Embodiment 22. The method of any one of Embodiments 16-21, comprising milling the scrap metal or used metal parts without embrittling the scrap metal or used metal parts by hydrogenation or applying cryogenics.
Embodiment 23. The method of any one of Embodiments 16-22, wherein the scrap metal or used metal parts comprise turnings resulting from subtractive manufacturing.
Embodiment 24. The method of any one of Embodiments 16-23, wherein the scrap metal or used metal parts comprises Ti-6-4.
Embodiment 25. A method of additive manufacturing, comprising using the spheroidized powder resulting from any one of Embodiments 16-24.
Embodiment 26. A method of laser bed fusion, comprising using the spheroidized powder resulting from any one of Embodiments 16-24.
Embodiment 27. A method of electron beam manufacturing, comprising using the spheroidized powder resulting from any one of Embodiments 16-24.
Embodiment 28. A method of metal injection molding, comprising using the spheroidized powder resulting from any one of Embodiments 15-23.
Embodiment 29. A method for manufacturing a spheroidized powder from scrap metal or used metal parts, the method comprising:
Embodiment 30. A spheroidized powder manufactured according to the method of any of Embodiments 1-24 or 29.
Embodiment 31. A method for manufacturing a spheroidized powder from used powder, the method comprising:
Embodiment 32. The method of Embodiment 31, wherein the previously used powder particles have a desired particle size distribution.
Embodiment 33. The method of any one of Embodiments 31-32, wherein the previously used powder particles comprise satellites, wherein the satellites are removed during the melting and spheroidizing.
Embodiment 34. The method of any one of Embodiments 31-33, wherein the previously used powder particles comprise agglomerations, wherein the agglomerations are removed during the melting and spheroidizing.
Embodiment 35. The method of any one of Embodiments 31-34, wherein the previously used powder particles comprise contaminants, wherein the contaminants are removed during the melting and spheroidizing.
Embodiment 36. The method of any one of Embodiments 31-35, wherein the previously used powder particles comprise metal or metal alloys.
Embodiment 37. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise titanium or titanium alloy.
Embodiment 38. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise nickel or nickel alloy.
Embodiment 39. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise a ductile metal or metal alloy.
Embodiment 40. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise cobalt or cobalt alloy.
Embodiment 41. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise steel and steel alloy.
Embodiment 42. The method of any one of Embodiments 31-36, wherein the previously used powder particles comprise a ceramic.
Embodiment 43. The method of any one of Embodiments 31-42, wherein the melting and spheroidizing improves flowability of the previously used powder particles.
Embodiment 44. The method of any one of Embodiments 31-43, wherein the melting and spheroidizing increases density of the previously used powder particles.
Embodiment 45. The method of any one of Embodiments 31-44, wherein carbon, nitrogen and/or other contaminants are removed from the previously used powder particles during the melting and spheroidizing.
Embodiment 46. The method of any one of Embodiments 31-45, wherein a noble gas, argon gas, a mixture of argon gas and hydrogen gas, or nitrogen gas is used during the melting and spheroidizing.
Embodiment 47. The method of any one of Embodiments 31-46, wherein the previously used powder particles were formed from an additive manufacturing process.
Embodiment 48. The method of Embodiment 47, wherein the additive manufacturing process comprises laser sintering, electron-beam melting, filament fused deposition, directed energy deposition, powder bed fusion, or binder jetting.
Embodiment 49. The method of any one of Embodiments 31-48, wherein the spheroidized powder particles retain the same rheological properties as the previously used powder particles after the melting and spheroidizing.
Embodiment 50. The method of any one of Embodiments 31-49, wherein alloy component chemistry and/or minor component chemistry being less than 10 wt % are the same in the spheroidized powder particles as the previously used powder particles.
Embodiment 51. The method of any one of Embodiments 31-50, wherein the previously used powder particles substantially only comprise particles that are not spheroidal.
Embodiment 52. The method of any one of Embodiments 31-50, wherein the previously used powder particles substantially only comprise particles that have satellites, contaminants, and/or agglomerations.
Embodiment 53. The method of any one of Embodiments 31-50, wherein the previously used powder particles comprise particles that are not spheroidal and particles that are spheroidal without having any satellites, contaminants, and/or agglomerations.
Embodiment 54. A method for producing a spheroidized powder from a feed material comprising dehydrogenated or non-hydrogenated titanium or titanium alloy, the method comprising:
Embodiment 55. The method of Embodiment 54, wherein the feed material comprises titanium or titanium alloy particles processed by the hydrogenation-dehydrogenation (HDH) process.
Embodiment 56. The method of any one of Embodiments 54-55, wherein the spheroidized powder comprises particles with a median sphericity of at least 0.75.
Embodiment 57. The method of any one of Embodiments 54-56, wherein the spheroidized powder comprises particles with a median sphericity of at least 0.91.
Embodiment 58. The method of any one of Embodiments 54-57, wherein the spheroidized powder has a particle size distribution of 15 to 45 microns.
Embodiment 59. The method of any one of Embodiments 54-58, wherein the spheroidized powder has a particle size distribution of 45 to 105 microns.
Embodiment 60. The method of any one of Embodiments 54-59, further comprising exposing the spheroidized particles to an inert gas.
Embodiment 61. The method of any one of Embodiments 54-60, further comprising setting one or more cooling processing variables to tailor the microstructure of the spheroidized particles.
Embodiment 62. The method of Embodiment 61, wherein setting one or more cooling processing variables comprises selecting and controlling a cooling gas flow rate.
Embodiment 63. The method of Embodiment 61, wherein setting one or more cooling processing variables comprises selecting and controlling a residence time of the particles of feed materials within the plasma.
Embodiment 64. The method of Embodiment 61, wherein setting one or more cooling processing variables comprises selecting and controlling a cooling gas composition.
Embodiment 65. The method of Embodiment 64, wherein the cooling gas composition is selected to provide high thermal conductivity.
Embodiment 66. The method of Embodiment 61, wherein one or more cooling processing variables are set to create a martensitic microstructure in the spheroidized particles.
Embodiment 67. The method of Embodiment 61, wherein one or more cooling processing variables are set to create a Widmanstätten microstructure in the spheroidized particles.
Embodiment 68. The method of Embodiment 61, wherein one or more cooling processing variables are set to create an equiaxed microstructure in the spheroidized particles.
Embodiment 69. The method of Embodiment 61, wherein one or more cooling processing variables are set to create at least two regions, each region having a different microstructure.
Embodiment 70. The method of Embodiment 69, wherein the at least two regions include a core portion and a skin portion.
Embodiment 71. The method of Embodiment 70, wherein the skin portion has a microstructure that is different from the feed material's microstructure.
Embodiment 72. The method of any one of Embodiments 54-71, wherein melting and spheroidizing of the particles occurs within a substantially uniform temperature profile between about 4,000K and 8,000K.
Embodiment 73. The method of any one of Embodiments 54-71, wherein the feed material has a particle size of no less than 1.0 microns and no more than 300 microns.
Embodiment 74. The method of any one of Embodiments 54-71, wherein the feed material comprises Ti-6-4, and wherein the melting and spheroidizing is controlled such that the spheroidized powder comprises Ti-6-4.
Embodiment 75. A spheroidized powder manufactured according to the method of any of Embodiments 31-74.
From the foregoing description, it will be appreciated that inventive processing methods for converting unique feedstocks to spheroidized powder are disclosed. While several components, techniques and aspects have been described with a certain degree of particularity, it is manifest that many changes can be made in the specific designs, constructions and methodology herein above described without departing from the spirit and scope of this disclosure.
Certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as any subcombination or variation of any subcombination.
Moreover, while methods may be depicted in the drawings or described in the specification in a particular order, such methods need not be performed in the particular order shown or in sequential order, and that all methods need not be performed, to achieve desirable results. Other methods that are not depicted or described can be incorporated in the example methods and processes. For example, one or more additional methods can be performed before, after, simultaneously, or between any of the described methods. Further, the methods may be rearranged or reordered in other implementations. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products. Additionally, other implementations are within the scope of this disclosure.
Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include or do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments.
Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.
Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, “generally,” and “substantially” may refer to an amount that is within less than or equal to 10% of, within less than or equal to 5% of, within less than or equal to 1% of, within less than or equal to 0.1% of, and within less than or equal to 0.01% of the stated amount. If the stated amount is 0 (e.g., none, having no), the above recited ranges can be specific ranges, and not within a particular % of the value. For example, within less than or equal to 10 wt./vol. % of, within less than or equal to 5 wt./vol. % of, within less than or equal to 1 wt./vol. % of, within less than or equal to 0.1 wt./vol. % of, and within less than or equal to 0.01 wt./vol. % of the stated amount.
The disclosure herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with various embodiments can be used in all other embodiments set forth herein. Additionally, it will be recognized that any methods described herein may be practiced using any device suitable for performing the recited steps.
While a number of embodiments and variations thereof have been described in detail, other modifications and methods of using the same will be apparent to those of skill in the art. Accordingly, it should be understood that various applications, modifications, materials, and substitutions can be made of equivalents without departing from the unique and inventive disclosure herein or the scope of the claims.
This application claims the priority benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 62/950,778, filed Dec. 19, 2019, the entire disclosure of which is incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
1699205 | Podszus et al. | Jul 1925 | A |
2892215 | Naeser et al. | Jun 1959 | A |
3290723 | Jacques et al. | Dec 1966 | A |
3293334 | Bylund et al. | Dec 1966 | A |
3434831 | Knopp et al. | Mar 1969 | A |
3466165 | Rhys et al. | Sep 1969 | A |
RE26879 | Kelso | May 1970 | E |
3652259 | Knopp | Mar 1972 | A |
3802816 | Kaufmann | Apr 1974 | A |
3845344 | Rainer | Oct 1974 | A |
3909241 | Cheney et al. | Sep 1975 | A |
3966374 | Honnorat et al. | Jun 1976 | A |
3974245 | Cheney et al. | Aug 1976 | A |
4076640 | Forgensi et al. | Feb 1978 | A |
4177026 | Honnorat et al. | Dec 1979 | A |
4212837 | Oguchi et al. | Jul 1980 | A |
4221554 | Oguchi et al. | Sep 1980 | A |
4221775 | Anno | Sep 1980 | A |
4423303 | Hirose et al. | Dec 1983 | A |
4431449 | Dillon et al. | Feb 1984 | A |
4439410 | Santen et al. | Mar 1984 | A |
4544404 | Yolton et al. | Oct 1985 | A |
4569823 | Westin | Feb 1986 | A |
4599880 | Stepanenko et al. | Jul 1986 | A |
4611108 | Leprince et al. | Sep 1986 | A |
4670047 | Kopatz et al. | Jun 1987 | A |
4692584 | Caneer, Jr. | Sep 1987 | A |
4705560 | Kemp, Jr. et al. | Nov 1987 | A |
4711660 | Kemp, Jr. et al. | Dec 1987 | A |
4711661 | Kemp, Jr. et al. | Dec 1987 | A |
4714587 | Eylon et al. | Dec 1987 | A |
4731110 | Kopatz et al. | Mar 1988 | A |
4731111 | Kopatz et al. | Mar 1988 | A |
4772315 | Johnson et al. | Sep 1988 | A |
4778515 | Kemp, Jr. et al. | Oct 1988 | A |
4780131 | Kemp, Jr. et al. | Oct 1988 | A |
4783216 | Kemp, Jr. et al. | Nov 1988 | A |
4783218 | Kemp, Jr. et al. | Nov 1988 | A |
4787934 | Johnson et al. | Nov 1988 | A |
4802915 | Kopatz et al. | Feb 1989 | A |
4836850 | Kemp, Jr. et al. | Jun 1989 | A |
4859237 | Johnson et al. | Aug 1989 | A |
4923509 | Kemp, Jr. et al. | May 1990 | A |
4943322 | Kemp, Jr. et al. | Jul 1990 | A |
4944797 | Kemp et al. | Jul 1990 | A |
4952389 | Szymanski et al. | Aug 1990 | A |
5041713 | Weidman | Aug 1991 | A |
5095048 | Takahashi et al. | Mar 1992 | A |
5114471 | Johnson et al. | May 1992 | A |
5131992 | Church et al. | Jul 1992 | A |
5200595 | Boulos et al. | Apr 1993 | A |
5290507 | Runkle | Mar 1994 | A |
5292370 | Tsai et al. | Mar 1994 | A |
5376475 | Ovshinsky et al. | Dec 1994 | A |
5411592 | Ovshinsky et al. | May 1995 | A |
5431967 | Manthiram et al. | Jul 1995 | A |
5518831 | Tou et al. | May 1996 | A |
5676919 | Kawamura et al. | Oct 1997 | A |
5750013 | Lin | May 1998 | A |
5776323 | Kobashi | Jul 1998 | A |
5958361 | Laine et al. | Sep 1999 | A |
5980977 | Deng et al. | Nov 1999 | A |
5989648 | Phillips | Nov 1999 | A |
6221125 | Soda et al. | Apr 2001 | B1 |
6261484 | Phillips et al. | Jul 2001 | B1 |
6274110 | Kim et al. | Aug 2001 | B1 |
6329628 | Kuo et al. | Dec 2001 | B1 |
6334882 | Aslund | Jan 2002 | B1 |
6376027 | Lee et al. | Apr 2002 | B1 |
6409851 | Sethuram et al. | Jun 2002 | B1 |
6428600 | Flurschutz et al. | Aug 2002 | B1 |
6543380 | Sung-Spritzl | Apr 2003 | B1 |
6551377 | Leonhardt | Apr 2003 | B1 |
6569397 | Yadav et al. | May 2003 | B1 |
6579573 | Strutt et al. | Jun 2003 | B2 |
6589311 | Han et al. | Jul 2003 | B1 |
6652822 | Phillips et al. | Nov 2003 | B2 |
6676728 | Han et al. | Jan 2004 | B2 |
6689192 | Phillips et al. | Feb 2004 | B1 |
6752979 | Talbot et al. | Jun 2004 | B1 |
6755886 | Phillips et al. | Jun 2004 | B2 |
6780219 | Singh et al. | Aug 2004 | B2 |
6793849 | Gruen et al. | Sep 2004 | B1 |
6805822 | Takei et al. | Oct 2004 | B2 |
6838072 | Kong et al. | Jan 2005 | B1 |
6869550 | Dorfman et al. | Mar 2005 | B2 |
6902745 | Lee et al. | Jun 2005 | B2 |
6919527 | Boulos et al. | Jul 2005 | B2 |
6989529 | Wiseman | Jan 2006 | B2 |
7066980 | Akimoto et al. | Jun 2006 | B2 |
7091441 | Kuo | Aug 2006 | B1 |
7108733 | Enokido | Sep 2006 | B2 |
7125537 | Liao et al. | Oct 2006 | B2 |
7125822 | Nakano et al. | Oct 2006 | B2 |
7175786 | Celikkaya et al. | Feb 2007 | B2 |
7182929 | Singhal et al. | Feb 2007 | B1 |
7220398 | Sutorik et al. | May 2007 | B2 |
7235118 | Bouaricha et al. | Jun 2007 | B2 |
7285194 | Uno et al. | Oct 2007 | B2 |
7285307 | Hohenthanner et al. | Oct 2007 | B2 |
7297310 | Peng et al. | Nov 2007 | B1 |
7297892 | Kelley et al. | Nov 2007 | B2 |
7344776 | Kollmann et al. | Mar 2008 | B2 |
7357910 | Phillips et al. | Apr 2008 | B2 |
7368130 | Kim et al. | May 2008 | B2 |
7374704 | Che et al. | May 2008 | B2 |
7375303 | Twarog | May 2008 | B2 |
7431750 | Liao et al. | Oct 2008 | B2 |
7442271 | Asmussen et al. | Oct 2008 | B2 |
7491468 | Okada et al. | Feb 2009 | B2 |
7517513 | Sarkas et al. | Apr 2009 | B2 |
7524353 | Johnson, Jr. et al. | Apr 2009 | B2 |
7534296 | Swain et al. | May 2009 | B2 |
7572315 | Boulos et al. | Aug 2009 | B2 |
7622211 | Vyas et al. | Nov 2009 | B2 |
7629553 | Fanson et al. | Dec 2009 | B2 |
7700152 | Laine et al. | Apr 2010 | B2 |
7776303 | Hung et al. | Aug 2010 | B2 |
7806077 | Lee et al. | Oct 2010 | B2 |
7828999 | Yubuta et al. | Nov 2010 | B2 |
7901658 | Weppner et al. | Mar 2011 | B2 |
7931836 | Xie et al. | Apr 2011 | B2 |
7939141 | Matthews et al. | May 2011 | B2 |
8007691 | Sawaki et al. | Aug 2011 | B2 |
8043405 | Johnson, Jr. et al. | Oct 2011 | B2 |
8092941 | Weppner et al. | Jan 2012 | B2 |
8101061 | Suh et al. | Jan 2012 | B2 |
8168128 | Seeley et al. | May 2012 | B2 |
8178240 | Wang et al. | May 2012 | B2 |
8192865 | Buiel et al. | Jun 2012 | B2 |
8193291 | Zhang | Jun 2012 | B2 |
8211388 | Woodfield et al. | Jul 2012 | B2 |
8268230 | Cherepy et al. | Sep 2012 | B2 |
8283275 | Heo et al. | Oct 2012 | B2 |
8303926 | Luhrs et al. | Nov 2012 | B1 |
8329090 | Hollingsworth et al. | Dec 2012 | B2 |
8329257 | Larouche et al. | Dec 2012 | B2 |
8338323 | Takasu et al. | Dec 2012 | B2 |
8389160 | Venkatachalam et al. | Mar 2013 | B2 |
8420043 | Gamo et al. | Apr 2013 | B2 |
8439998 | Ito et al. | May 2013 | B2 |
8449950 | Shang et al. | May 2013 | B2 |
8478785 | Jamjoom et al. | Jul 2013 | B2 |
8492303 | Bulan et al. | Jul 2013 | B2 |
8529996 | Bocian et al. | Sep 2013 | B2 |
8592767 | Rappe et al. | Nov 2013 | B2 |
8597722 | Albano et al. | Dec 2013 | B2 |
8623555 | Kang et al. | Jan 2014 | B2 |
8658317 | Weppner et al. | Feb 2014 | B2 |
8685593 | Dadheech et al. | Apr 2014 | B2 |
8728680 | Mikhail et al. | May 2014 | B2 |
8735022 | Schlag et al. | May 2014 | B2 |
8748785 | Jordan et al. | Jun 2014 | B2 |
8758957 | Dadheech et al. | Jun 2014 | B2 |
8784706 | Shevchenko et al. | Jul 2014 | B2 |
8822000 | Kumagai et al. | Sep 2014 | B2 |
8840701 | Borland et al. | Sep 2014 | B2 |
8877119 | Jordan et al. | Nov 2014 | B2 |
8911529 | Withers et al. | Dec 2014 | B2 |
8919428 | Cola et al. | Dec 2014 | B2 |
8945431 | Schulz et al. | Feb 2015 | B2 |
8951496 | Hadidi et al. | Feb 2015 | B2 |
8956785 | Dadheech et al. | Feb 2015 | B2 |
8968587 | Shin et al. | Mar 2015 | B2 |
8968669 | Chen | Mar 2015 | B2 |
8980485 | Lanning et al. | Mar 2015 | B2 |
8999440 | Zenasni et al. | Apr 2015 | B2 |
9023259 | Hadidi et al. | May 2015 | B2 |
9065141 | Merzougui et al. | Jun 2015 | B2 |
9067264 | Moxson et al. | Jun 2015 | B2 |
9079778 | Kelley et al. | Jul 2015 | B2 |
9085490 | Taylor et al. | Jul 2015 | B2 |
9101982 | Aslund | Aug 2015 | B2 |
9136569 | Song et al. | Sep 2015 | B2 |
9150422 | Nakayama et al. | Oct 2015 | B2 |
9193133 | Shin et al. | Nov 2015 | B2 |
9196901 | Se-Hee et al. | Nov 2015 | B2 |
9196905 | Tzeng et al. | Nov 2015 | B2 |
9206085 | Hadidi et al. | Dec 2015 | B2 |
9242224 | Redjdal et al. | Jan 2016 | B2 |
9259785 | Hadidi et al. | Feb 2016 | B2 |
9321071 | Jordan et al. | Apr 2016 | B2 |
9322081 | McHugh et al. | Apr 2016 | B2 |
9352278 | Spatz et al. | May 2016 | B2 |
9356281 | Verbrugge et al. | May 2016 | B2 |
9368772 | Chen et al. | Jun 2016 | B1 |
9412998 | Rojeski et al. | Aug 2016 | B2 |
9421612 | Fang et al. | Aug 2016 | B2 |
9425463 | Hsu et al. | Aug 2016 | B2 |
9463435 | Schulz et al. | Oct 2016 | B2 |
9520600 | Dadheech et al. | Dec 2016 | B2 |
9624565 | Lee et al. | Apr 2017 | B2 |
9630162 | Sunkara et al. | Apr 2017 | B1 |
9643891 | Hadidi et al. | May 2017 | B2 |
9700877 | Kim et al. | Jul 2017 | B2 |
9705136 | Rojeski | Jul 2017 | B2 |
9718131 | Boulos et al. | Aug 2017 | B2 |
9735427 | Zhang | Aug 2017 | B2 |
9751129 | Boulos et al. | Sep 2017 | B2 |
9768033 | Ranjan et al. | Sep 2017 | B2 |
9776378 | Choi | Oct 2017 | B2 |
9782791 | Redjdal et al. | Oct 2017 | B2 |
9782828 | Wilkinson | Oct 2017 | B2 |
9796019 | She et al. | Oct 2017 | B2 |
9796020 | Aslund | Oct 2017 | B2 |
9831503 | Sopchak | Nov 2017 | B2 |
9871248 | Rayner et al. | Jan 2018 | B2 |
9879344 | Lee et al. | Jan 2018 | B2 |
9899674 | Hirai et al. | Feb 2018 | B2 |
9917299 | Behan et al. | Mar 2018 | B2 |
9932673 | Jordan et al. | Apr 2018 | B2 |
9945034 | Yao et al. | Apr 2018 | B2 |
9947926 | Kim et al. | Apr 2018 | B2 |
9981284 | Guo et al. | May 2018 | B2 |
9991458 | Rosenman et al. | Jun 2018 | B2 |
9999922 | Struve | Jun 2018 | B1 |
10011491 | Lee et al. | Jul 2018 | B2 |
10050303 | Anandan et al. | Aug 2018 | B2 |
10057986 | Prud'Homme et al. | Aug 2018 | B2 |
10065240 | Chen | Sep 2018 | B2 |
10079392 | Huang et al. | Sep 2018 | B2 |
10116000 | Federici et al. | Oct 2018 | B1 |
10130994 | Fang et al. | Nov 2018 | B2 |
10167556 | Ruzic et al. | Jan 2019 | B2 |
10170753 | Ren et al. | Jan 2019 | B2 |
10193142 | Rojeski | Jan 2019 | B2 |
10244614 | Foret | Mar 2019 | B2 |
10319537 | Claussen et al. | Jun 2019 | B2 |
10333183 | Sloop | Jun 2019 | B2 |
10350680 | Yamamoto et al. | Jul 2019 | B2 |
10411253 | Tzeng et al. | Sep 2019 | B2 |
10439206 | Behan et al. | Oct 2019 | B2 |
10442000 | Fukada et al. | Oct 2019 | B2 |
10461298 | Herle | Oct 2019 | B2 |
10477665 | Hadidi | Nov 2019 | B2 |
10493524 | She et al. | Dec 2019 | B2 |
10522300 | Yang | Dec 2019 | B2 |
10526684 | Ekman et al. | Jan 2020 | B2 |
10529486 | Nishisaka | Jan 2020 | B2 |
10543534 | Hadidi et al. | Jan 2020 | B2 |
10593985 | Sastry et al. | Mar 2020 | B2 |
10610929 | Fang et al. | Apr 2020 | B2 |
10637029 | Gotlib Vainshtein et al. | Apr 2020 | B2 |
10638592 | Foret | Apr 2020 | B2 |
10639712 | Barnes et al. | May 2020 | B2 |
10647824 | Hwang et al. | May 2020 | B2 |
10655206 | Moon et al. | May 2020 | B2 |
10665890 | Kang et al. | May 2020 | B2 |
10668566 | Smathers et al. | Jun 2020 | B2 |
10669437 | Cox et al. | Jun 2020 | B2 |
10688564 | Boulos et al. | Jun 2020 | B2 |
10707477 | Sastry et al. | Jul 2020 | B2 |
10717150 | Aleksandrov et al. | Jul 2020 | B2 |
10727477 | Kim et al. | Jul 2020 | B2 |
10741845 | Yushin et al. | Aug 2020 | B2 |
10744590 | Maier et al. | Aug 2020 | B2 |
10756334 | Stowell et al. | Aug 2020 | B2 |
10766787 | Sunkara et al. | Sep 2020 | B1 |
10777804 | Sastry et al. | Sep 2020 | B2 |
10892477 | Choi et al. | Jan 2021 | B2 |
10943744 | Sungail et al. | Mar 2021 | B2 |
10944093 | Paz et al. | Mar 2021 | B2 |
10964938 | Rojeski | Mar 2021 | B2 |
10987735 | Hadidi et al. | Apr 2021 | B2 |
10998552 | Lanning et al. | May 2021 | B2 |
11031641 | Gupta et al. | Jun 2021 | B2 |
11050061 | Kim et al. | Jun 2021 | B2 |
11072533 | Shevchenko et al. | Jul 2021 | B2 |
11077524 | Smathers et al. | Aug 2021 | B2 |
11108050 | Kim et al. | Aug 2021 | B2 |
11130175 | Parrish et al. | Sep 2021 | B2 |
11133495 | Gazda et al. | Sep 2021 | B2 |
11148202 | Hadidi et al. | Oct 2021 | B2 |
11171322 | Seol et al. | Nov 2021 | B2 |
11183682 | Sunkara et al. | Nov 2021 | B2 |
11196045 | Dadheech et al. | Dec 2021 | B2 |
11219884 | Takeda et al. | Jan 2022 | B2 |
11245065 | Ouderkirk et al. | Feb 2022 | B1 |
11245109 | Tzeng et al. | Feb 2022 | B2 |
11254585 | Ekman et al. | Feb 2022 | B2 |
11273322 | Zanata et al. | Mar 2022 | B2 |
11273491 | Barnes et al. | Mar 2022 | B2 |
11299397 | Lanning et al. | Apr 2022 | B2 |
11311938 | Badwe et al. | Apr 2022 | B2 |
11335911 | Lanning et al. | May 2022 | B2 |
11465201 | Barnes et al. | Oct 2022 | B2 |
11471941 | Barnet et al. | Oct 2022 | B2 |
20010016283 | Shiraishi et al. | Aug 2001 | A1 |
20020112794 | Sethuram et al. | Aug 2002 | A1 |
20030027021 | Sharivker et al. | Feb 2003 | A1 |
20030129497 | Yamamoto et al. | Jul 2003 | A1 |
20030172772 | Sethuram et al. | Sep 2003 | A1 |
20030186128 | Singh et al. | Oct 2003 | A1 |
20030207978 | Yadav et al. | Nov 2003 | A1 |
20040013941 | Kobayashi et al. | Jan 2004 | A1 |
20040045807 | Sarkas et al. | Mar 2004 | A1 |
20040123699 | Liao et al. | Jul 2004 | A1 |
20050025698 | Talbot et al. | Feb 2005 | A1 |
20050163696 | Uhm et al. | Jul 2005 | A1 |
20050242070 | Hammer | Nov 2005 | A1 |
20050260786 | Yoshikawa et al. | Nov 2005 | A1 |
20060040168 | Sridhar | Feb 2006 | A1 |
20060141153 | Kubota et al. | Jun 2006 | A1 |
20060145124 | Hsiao et al. | Jul 2006 | A1 |
20060291827 | Suib et al. | Dec 2006 | A1 |
20070077350 | Hohenthanner et al. | Apr 2007 | A1 |
20070089860 | Hou et al. | Apr 2007 | A1 |
20070209758 | Sompalli et al. | Sep 2007 | A1 |
20070259768 | Kear et al. | Nov 2007 | A1 |
20080029485 | Kelley et al. | Feb 2008 | A1 |
20080182114 | Kim et al. | Jul 2008 | A1 |
20080220244 | Wai et al. | Sep 2008 | A1 |
20080286490 | Bogdanoff et al. | Nov 2008 | A1 |
20080296268 | Mike et al. | Dec 2008 | A1 |
20080305025 | Vitner et al. | Dec 2008 | A1 |
20090074655 | Suciu | Mar 2009 | A1 |
20090093553 | Jager et al. | Apr 2009 | A1 |
20090155689 | Zaghib et al. | Jun 2009 | A1 |
20090202869 | Sawaki et al. | Aug 2009 | A1 |
20090258255 | Terashima et al. | Oct 2009 | A1 |
20090305132 | Gauthier et al. | Dec 2009 | A1 |
20100007162 | Han et al. | Jan 2010 | A1 |
20100096362 | Hirayama et al. | Apr 2010 | A1 |
20100176524 | Burgess et al. | Jul 2010 | A1 |
20110006254 | Richard et al. | Jan 2011 | A1 |
20120015284 | Merzougui et al. | Jan 2012 | A1 |
20120027955 | Sunkara et al. | Feb 2012 | A1 |
20120034135 | Risby | Feb 2012 | A1 |
20120048064 | Kasper et al. | Mar 2012 | A1 |
20120051962 | Imam et al. | Mar 2012 | A1 |
20120074342 | Kim et al. | Mar 2012 | A1 |
20120100438 | Fasching et al. | Apr 2012 | A1 |
20120122017 | Mills | May 2012 | A1 |
20120230860 | Ward-Close et al. | Sep 2012 | A1 |
20120240726 | Kim et al. | Sep 2012 | A1 |
20120294919 | Jaynes et al. | Nov 2012 | A1 |
20130032753 | Yamamoto et al. | Feb 2013 | A1 |
20130071284 | Kano et al. | Mar 2013 | A1 |
20130078508 | Tolbert et al. | Mar 2013 | A1 |
20130084474 | Mills | Apr 2013 | A1 |
20140202286 | Yokoyama et al. | Jul 2014 | A1 |
20140272430 | Kalayaraman | Sep 2014 | A1 |
20140322632 | Sugimoto et al. | Oct 2014 | A1 |
20150000844 | Woo | Jan 2015 | A1 |
20150101454 | Shimizu et al. | Apr 2015 | A1 |
20150171455 | Mills | Jun 2015 | A1 |
20150255767 | Aetukuri et al. | Sep 2015 | A1 |
20150259220 | Rosocha et al. | Sep 2015 | A1 |
20150333307 | Thokchom et al. | Nov 2015 | A1 |
20160028088 | Romeo et al. | Jan 2016 | A1 |
20160152480 | Jang et al. | Jun 2016 | A1 |
20160285090 | Ozkan et al. | Sep 2016 | A1 |
20160287113 | Hebert et al. | Oct 2016 | A1 |
20160308244 | Badding et al. | Oct 2016 | A1 |
20160332232 | Forbes Jones et al. | Nov 2016 | A1 |
20160351910 | Albano et al. | Dec 2016 | A1 |
20170009328 | Germann et al. | Jan 2017 | A1 |
20170070180 | Mills | Mar 2017 | A1 |
20170120339 | Aslund | May 2017 | A1 |
20170125842 | Meguro et al. | May 2017 | A1 |
20170151609 | Elsen et al. | Jun 2017 | A1 |
20170173699 | Hadidi et al. | Jun 2017 | A1 |
20170176977 | Huang et al. | Jun 2017 | A1 |
20170179477 | Walters et al. | Jun 2017 | A1 |
20170209963 | Smathers et al. | Jul 2017 | A1 |
20170368604 | Wilkinson | Dec 2017 | A1 |
20170373344 | Hadidi et al. | Dec 2017 | A1 |
20180083264 | Soppe | Mar 2018 | A1 |
20180104745 | L'Esperance et al. | Apr 2018 | A1 |
20180159178 | Weisenstein et al. | Jun 2018 | A1 |
20180214956 | Larouche et al. | Aug 2018 | A1 |
20180241956 | Suzuki | Aug 2018 | A1 |
20180248175 | Ghezelbash et al. | Aug 2018 | A1 |
20180277849 | Gayden | Sep 2018 | A1 |
20180297122 | Hadidi et al. | Oct 2018 | A1 |
20180366707 | Johnson et al. | Dec 2018 | A1 |
20190001416 | Larouche et al. | Jan 2019 | A1 |
20190061005 | Kelkar | Feb 2019 | A1 |
20190084290 | Stoyanov et al. | Mar 2019 | A1 |
20190125842 | Grabowski | May 2019 | A1 |
20190127835 | Yang et al. | May 2019 | A1 |
20190160528 | McGee et al. | May 2019 | A1 |
20190165413 | Furusawa | May 2019 | A1 |
20190173130 | Schuhmacher et al. | Jun 2019 | A1 |
20190217389 | Parrish et al. | Jul 2019 | A1 |
20190218650 | Subramanian et al. | Jul 2019 | A1 |
20190271068 | Sungail et al. | Sep 2019 | A1 |
20190292441 | Hill et al. | Sep 2019 | A1 |
20190334206 | Sastry et al. | Oct 2019 | A1 |
20190341650 | Lanning et al. | Nov 2019 | A9 |
20190348202 | Sachdev et al. | Nov 2019 | A1 |
20200067128 | Chmiola et al. | Feb 2020 | A1 |
20200153037 | Renna et al. | May 2020 | A1 |
20200198977 | Hof et al. | Jun 2020 | A1 |
20200203706 | Holman et al. | Jun 2020 | A1 |
20200207668 | Cavalli et al. | Jul 2020 | A1 |
20200215606 | Barnes et al. | Jul 2020 | A1 |
20200223704 | Neale et al. | Jul 2020 | A1 |
20200227728 | Huang et al. | Jul 2020 | A1 |
20200254432 | Shirman et al. | Aug 2020 | A1 |
20200276638 | King et al. | Sep 2020 | A1 |
20200288561 | Huh | Sep 2020 | A1 |
20200314991 | Duanmu et al. | Oct 2020 | A1 |
20200335754 | Ramasubramanian et al. | Oct 2020 | A1 |
20200335781 | Oshita et al. | Oct 2020 | A1 |
20200346287 | Badwe et al. | Nov 2020 | A1 |
20200350542 | Wrobel et al. | Nov 2020 | A1 |
20200350565 | Oshita et al. | Nov 2020 | A1 |
20200358093 | Oshita et al. | Nov 2020 | A1 |
20200358096 | Paulsen et al. | Nov 2020 | A1 |
20200388857 | Sunkara et al. | Dec 2020 | A1 |
20200391295 | Dorval Dion | Dec 2020 | A1 |
20200395607 | Tzeng | Dec 2020 | A1 |
20200407858 | Sano et al. | Dec 2020 | A1 |
20210047186 | Ifuku et al. | Feb 2021 | A1 |
20210075000 | Holman et al. | Mar 2021 | A1 |
20210078072 | Barnes et al. | Mar 2021 | A1 |
20210085468 | Ryd et al. | Mar 2021 | A1 |
20210129216 | Barnes et al. | May 2021 | A1 |
20210139331 | Kang et al. | May 2021 | A1 |
20210146432 | Badwe et al. | May 2021 | A1 |
20210226302 | Lanning et al. | Jul 2021 | A1 |
20210252599 | Hadidi et al. | Aug 2021 | A1 |
20210253430 | Zaplotnik et al. | Aug 2021 | A1 |
20210273292 | Yun et al. | Sep 2021 | A1 |
20210276094 | Sobu et al. | Sep 2021 | A1 |
20210296731 | Wrobel et al. | Sep 2021 | A1 |
20210310110 | Stowell et al. | Oct 2021 | A1 |
20210344059 | Ekman et al. | Nov 2021 | A1 |
20210367264 | Hadidi et al. | Nov 2021 | A1 |
20210408533 | Holman et al. | Dec 2021 | A1 |
20220041457 | Pullen et al. | Feb 2022 | A1 |
20220095445 | Shang et al. | Mar 2022 | A1 |
20220118517 | Hadidi et al. | Apr 2022 | A1 |
20220127145 | Ding et al. | Apr 2022 | A1 |
20220134431 | Badwe et al. | May 2022 | A1 |
20220223379 | Holman et al. | Jul 2022 | A1 |
20220228288 | Holman et al. | Jul 2022 | A1 |
20220267216 | Holman et al. | Aug 2022 | A1 |
20220288685 | Badwe | Sep 2022 | A1 |
20220314325 | Badwe | Oct 2022 | A1 |
20220324022 | Badwe | Oct 2022 | A1 |
Number | Date | Country |
---|---|---|
2003211869 | Sep 2003 | AU |
2014394102 | Jun 2020 | AU |
2947531 | Nov 2015 | CA |
1188073 | Jul 1998 | CN |
1653869 | Aug 2005 | CN |
1675785 | Sep 2005 | CN |
1967911 | May 2007 | CN |
101191204 | Jun 2008 | CN |
101391307 | Mar 2009 | CN |
101728509 | Jun 2010 | CN |
101716686 | Feb 2011 | CN |
102394290 | Mar 2012 | CN |
102412377 | Apr 2012 | CN |
102427130 | Apr 2012 | CN |
102664273 | Sep 2012 | CN |
102723502 | Oct 2012 | CN |
102179521 | Jan 2013 | CN |
102867940 | Jan 2013 | CN |
102983312 | Mar 2013 | CN |
103402921 | Nov 2013 | CN |
102554242 | Dec 2013 | CN |
103456926 | Dec 2013 | CN |
103682372 | Mar 2014 | CN |
103682383 | Mar 2014 | CN |
103700815 | Apr 2014 | CN |
103874538 | Jun 2014 | CN |
103956520 | Jul 2014 | CN |
104064736 | Sep 2014 | CN |
104084592 | Oct 2014 | CN |
104209526 | Dec 2014 | CN |
104218213 | Dec 2014 | CN |
204156003 | Feb 2015 | CN |
104485452 | Apr 2015 | CN |
104752734 | Jul 2015 | CN |
103515590 | Sep 2015 | CN |
105514373 | Apr 2016 | CN |
104772473 | Sep 2016 | CN |
106159316 | Nov 2016 | CN |
106450146 | Feb 2017 | CN |
106493350 | Mar 2017 | CN |
206040854 | Mar 2017 | CN |
106684387 | May 2017 | CN |
106784692 | May 2017 | CN |
107093732 | Aug 2017 | CN |
107579241 | Jan 2018 | CN |
108134104 | Jun 2018 | CN |
108217612 | Jun 2018 | CN |
108649190 | Oct 2018 | CN |
108963239 | Dec 2018 | CN |
109167070 | Jan 2019 | CN |
109301212 | Feb 2019 | CN |
109616622 | Apr 2019 | CN |
109742320 | May 2019 | CN |
109888233 | Jun 2019 | CN |
110299516 | Oct 2019 | CN |
110790263 | Feb 2020 | CN |
110993908 | Apr 2020 | CN |
111099577 | May 2020 | CN |
111342163 | Jun 2020 | CN |
111370751 | Jul 2020 | CN |
111403701 | Jul 2020 | CN |
111970807 | Nov 2020 | CN |
112259740 | Jan 2021 | CN |
112331947 | Feb 2021 | CN |
112397706 | Feb 2021 | CN |
112421006 | Feb 2021 | CN |
112421048 | Feb 2021 | CN |
112447977 | Mar 2021 | CN |
112768709 | May 2021 | CN |
112768710 | May 2021 | CN |
112768711 | May 2021 | CN |
112864453 | May 2021 | CN |
113097487 | Jul 2021 | CN |
113104838 | Jul 2021 | CN |
113764688 | Dec 2021 | CN |
113871581 | Dec 2021 | CN |
114388822 | Apr 2022 | CN |
114744315 | Jul 2022 | CN |
114824297 | Jul 2022 | CN |
10335355 | Nov 2004 | DE |
102009033251 | Sep 2010 | DE |
102010006440 | Aug 2011 | DE |
102011109137 | Feb 2013 | DE |
102018132896 | Jun 2020 | DE |
0 256 233 | Feb 1988 | EP |
2 292 557 | Mar 2011 | EP |
3 143 838 | Mar 2017 | EP |
2591412 | Jun 1987 | FR |
2595745 | Dec 2021 | GB |
202011017775 | Oct 2021 | IN |
10-172564 | Jun 1998 | JP |
11-064556 | Mar 1999 | JP |
2001-348296 | Dec 2001 | JP |
2004-505761 | Feb 2004 | JP |
2004-193115 | Jul 2004 | JP |
2004-311297 | Nov 2004 | JP |
2004-362895 | Dec 2004 | JP |
2005-015282 | Jan 2005 | JP |
2005-072015 | Mar 2005 | JP |
2005-135755 | May 2005 | JP |
2005-187295 | Jul 2005 | JP |
2005-222956 | Aug 2005 | JP |
2005-272284 | Oct 2005 | JP |
2006-040722 | Feb 2006 | JP |
2007-138287 | Jun 2007 | JP |
2007-149513 | Jun 2007 | JP |
2007-238402 | Sep 2007 | JP |
2008-230905 | Oct 2008 | JP |
2008-243447 | Oct 2008 | JP |
2009-187754 | Aug 2009 | JP |
2010-024506 | Feb 2010 | JP |
2010-097914 | Apr 2010 | JP |
2011-108406 | Jun 2011 | JP |
2011-222323 | Nov 2011 | JP |
2011-258348 | Dec 2011 | JP |
2012-046393 | Mar 2012 | JP |
2012-151052 | Aug 2012 | JP |
2013-062242 | Apr 2013 | JP |
2013-063539 | Apr 2013 | JP |
2013-076130 | Apr 2013 | JP |
2015-048269 | Mar 2015 | JP |
2015-122218 | Jul 2015 | JP |
2016-047961 | Apr 2016 | JP |
2017-524628 | Aug 2017 | JP |
2018-141762 | Sep 2018 | JP |
2018-190563 | Nov 2018 | JP |
2020-121898 | Aug 2020 | JP |
2021-061089 | Apr 2021 | JP |
2021-061090 | Apr 2021 | JP |
2021-116191 | Aug 2021 | JP |
10-2007-0076686 | Jul 2007 | KR |
10-2009-0070140 | Jul 2009 | KR |
10-1133094 | Apr 2012 | KR |
10-2017-0039922 | Apr 2017 | KR |
2018-0001799 | Jan 2018 | KR |
10-1907912 | Oct 2018 | KR |
10-1907916 | Oct 2018 | KR |
10-1923466 | Nov 2018 | KR |
10-2101006 | Apr 2020 | KR |
10-2124946 | Jun 2020 | KR |
10-2020-0131751 | Nov 2020 | KR |
10-2021-0057253 | May 2021 | KR |
2744449 | Mar 2021 | RU |
521539 | Feb 2003 | TW |
200823313 | Jun 2008 | TW |
I329143 | Aug 2010 | TW |
201411922 | Mar 2014 | TW |
0377333 | Sep 2003 | WO |
2004054017 | Jun 2004 | WO |
2004089821 | Oct 2004 | WO |
WO 2005039752 | May 2005 | WO |
2006100837 | Sep 2006 | WO |
2011090779 | Jul 2011 | WO |
WO 2011082596 | Jul 2011 | WO |
2012114108 | Aug 2012 | WO |
WO 2012144424 | Oct 2012 | WO |
2012162743 | Dec 2012 | WO |
2013017217 | Feb 2013 | WO |
2014011239 | Jan 2014 | WO |
2014110604 | Jul 2014 | WO |
2014153318 | Sep 2014 | WO |
WO 2015064633 | May 2015 | WO |
WO 2015174949 | Nov 2015 | WO |
WO 2016048862 | Mar 2016 | WO |
2016091957 | Jun 2016 | WO |
2017074081 | May 2017 | WO |
2017074084 | May 2017 | WO |
2017080978 | May 2017 | WO |
WO 2017091543 | Jun 2017 | WO |
WO 2017106601 | Jun 2017 | WO |
2017118955 | Jul 2017 | WO |
WO 2017177315 | Oct 2017 | WO |
WO 2017223482 | Dec 2017 | WO |
2018133429 | Jul 2018 | WO |
WO 2018141082 | Aug 2018 | WO |
2019052670 | Mar 2019 | WO |
WO 2019045923 | Mar 2019 | WO |
WO 2019095039 | May 2019 | WO |
WO 2019139773 | Jul 2019 | WO |
WO 2019243870 | Dec 2019 | WO |
WO 2019246242 | Dec 2019 | WO |
WO 2019246257 | Dec 2019 | WO |
WO 2020009955 | Jan 2020 | WO |
2020041767 | Feb 2020 | WO |
2020041775 | Feb 2020 | WO |
WO 2020091854 | May 2020 | WO |
WO 2020132343 | Jun 2020 | WO |
WO 2020223358 | Nov 2020 | WO |
WO 2020223374 | Nov 2020 | WO |
2021029769 | Feb 2021 | WO |
WO 2021046249 | Mar 2021 | WO |
2021085670 | May 2021 | WO |
2021115596 | Jun 2021 | WO |
WO 2021118762 | Jun 2021 | WO |
WO 2021127132 | Jun 2021 | WO |
2021191281 | Sep 2021 | WO |
2021245410 | Dec 2021 | WO |
2021245411 | Dec 2021 | WO |
WO 2021263273 | Dec 2021 | WO |
2022005999 | Jan 2022 | WO |
2022032301 | Feb 2022 | WO |
2022043701 | Mar 2022 | WO |
2022043702 | Mar 2022 | WO |
2022043704 | Mar 2022 | WO |
2022043705 | Mar 2022 | WO |
2022067303 | Mar 2022 | WO |
2022075846 | Apr 2022 | WO |
2022107907 | May 2022 | WO |
2022133585 | Jun 2022 | WO |
2022136699 | Jun 2022 | WO |
Entry |
---|
Bobzin, K. et al., “Modelling and Diagnostics of Multiple Cathodes Plasma Torch System for Plasma Spraying”, Frontiers of Mechanical Engineering, Sep. 2011, vol. 6, pp. 324-331. |
Bobzin, K. et al., “Numerical and Experimental Determination of Plasma Temperature during Air Plasma Spraying with a Multiple Cathodes Torch”, Journal of Materials Processing Technology, Oct. 2011, vol. 211, pp. 1620-1628. |
Boulos, M., “Plasma power can make better powders”, Metal Powder Report, May 2004, vol. 59(5), pp. 16-21. |
Coldwell, D. M. et al., “The reduction of SiO2 with Carbon in a Plasma”, Journal of Electrochemical Society, Jan. 1977, vol. 124, pp. 1686-1689. |
Gradl, P. et al., “GRCop-42 Development and Hot-fire Testing Using Additive Manufacturing Powder Bed Fusion for Channel-Cooled Combustion Chambers”, 55th AIAA/SAE/ASEE Joint Propulsion Conference 2019, Aug. 2019, pp. 1-26. |
Li, L .et al., “Spheroidization of silica powders by radio frequency inductively coupled plasma with Ar—H2 and Ar—N2 as the sheath gases at atmospheric pressure”, International Journal of Minerals, Metallurgy, and Materials, Sep. 2017, vol. 24(9), pp. 1067-1074. |
Moisan, M. et al., “Waveguide-Based Single and Multiple Nozzle Plasma Torches: the Tiago Concept”, Plasma Sources Science and Technology, Jun. 2001, vol. 10, pp. 387-394. |
Zielinski, A. et al., “Modeling and Analysis of a Dual-Channel Plasma Torch in Pulsed Mode Operation for Industrial, Space, and Launch Applications”, IEEE Transactions on Plasma Science, Jul. 2015, vol. 43(7), pp. 2201-2206. |
European Office Action, re EP Application No. 18923334.9, dated Dec. 9, 2021. |
International Search Report and Written Opinion, re PCT Application No. PCT/2020/065536, dated Mar. 5, 2021. |
“Build Boldly”, Technology Demonstration, 6K Additive, [publication date unknown], in 11 pages. |
Fuchs, G.E. et al., “Microstructural evaluation of as-solidified and heat-treated y-TiAl based powders”, Materials Science and Engineering, 1992, A152, pp. 277-282. |
Jia, H. et al., “Hierarchical porous silicon structures with extraordinary mechanical strength as high-performance lithium-ion battery anodes”, Nature Communications, Mar. 2020, vol. 11, in 9 pages. URL: https://doi.org/10.1038/s41467-020-15217-9. |
Ko, M. et al., “Challenges in Accommodating Volume Change of Si Anodes for Li-Ion Batteries”, Chern Electro Chern, Aug. 2015, vol. 2, pp. 1645-1651. URL: https://doi.org/10.1002/celc.201500254. |
Li, X. et al., “Mesoporous silicon sponge as an anti-pulverization structure for high-performance lithium-ion battery anodes”, Nature Communications, Jul. 2014, vol. 5, Article No. 4105, in 7 pages. URL: https://doi.org/10.1038/ncomms5105. |
Li, Z. et al., “Strong and Ductile Non-Equiatomic High-Entropy Alloys: Design, Processing, Microstructure, and Mechanical Properties”, The Journal of the Minerals, Metals & Materials Society, Aug. 2017, vol. 69(1), pp. 2099-2106. URL: https://doi.org/10.1007/s11837-017-2540-2. |
Ohta, R. et al., “Effect of PS-PVD production throughput on Si nanoparticles for negative electrode of lithium ion batteries”, Journal of Physics D: Applied Physics, Feb. 2018, vol. 51(1), in 7 pages. |
Or, T. et al., “Recycling of mixed cathode lithium-ion batteries for electric vehicles: Current status and future outlook”, Carbon Energy, Jan. 2020, vol. 2, pp. 6-43. URL: https://doi.org/10.1002/cey2.29. |
Sastry, S.M.L et al., “Rapid Solidification Processing of Titanium Alloys”, Journal of Metals (JOM), Sep. 1983, vol. 35, pp. 21-28. |
Savage, S. J. et al., “Production of rapidly solidified metals and alloys”, Journal of Metals (JOM), Apr. 1984, vol. 36, pp. 20-33. |
Suryanarayana, C. et al., “Rapid solidification processing of titanium alloys”, International Materials Reviews, 1991, vol. 36, pp. 85-123. |
Tang, H. P. et al., “Effect of Powder Reuse Times on Additive Manufacturing of Ti-6Al-4V by Selective Electron Beam Melting”, JOM, Mar. 2015, vol. 67, pp. 555-563. |
Wang, Y. et al., “Developments in Nanostructured Cathode Materials for High-Performance Lithium-Ion Batteries”, Advanced Materials, Jun. 2008, pp. 2251-2269. |
Zhang, Y. et al., “Microstructures and properties of high-entropy alloys”, Progress in Materials Science, Apr. 2014 (available online Nov. 2013), vol. 61, pp. 1-93. |
Zhang, Y. D. et al., “High-energy cathode materials for Li-ion batteries: A review of recent developments”, Science China Technological Sciences, Sep. 2015, vol. 58(11), pp. 1809-1828. |
Australian Office Action, re AU Application No. 2016370962, dated May 29, 2020. |
Chinese Office Action, re CN Application No. 201680082035.1, dated Sep. 2, 2020. |
Chinese Office Action, re CN Application No. 201680082035.1, dated Mar. 11, 2021. |
Chinese Office Action, re CN Application No. 201680082035.1, dated Sep. 7, 2021. |
European Office Action, re EP Application No. 16876747.3, dated Jun. 12, 2019. |
European Office Action, re EP Application No. 16876747.3, dated May 18, 2020. |
European Office Action, re EP Application No. 16876747.3, dated Jan. 26, 2021. |
European Office Action, re EP Application No. 16876747.3, dated Sep. 8, 2021. |
Ajayi, B. et al., “A rapid and scalable method for making mixed metal oxide alloys for enabling accelerated materials discovery”, Journal of Materials Research, Jun. 2016, vol. 31, No. 11, pp. 1596-1607. |
Boulos, M., “The inductively coupled radio frequency plasma”, Journal of High Temperature Material Process, 1997, vol. 1, pp. 17-39. |
Boulos, M., “Induction Plasma Processing of Materials for Powders, Coating, and Near-Net-Shape Parts”, Advanced Materials & Processes, Aug. 2011, pp. 52-53, in 3 pages. |
Carreon, H et al., “Study of Aging Effects in a Ti-6AL-4V alloy with Widmanstatten and Equiaxed Microstructures by Non-destructive Means”, AIP Conference Proceedings 1581, 2014 (published online Feb. 17, 2015), pp. 739-745. |
Chang, S. et al., “One-Step Fast Synthesis of Li4Ti5O12 Particles Using an Atmospheric Pressure Plasma Jet”, Journal of the American Ceramic Society, Dec. 26, 2013, vol. 97, No. 3, pp. 708-712. |
Chen, G. et al., “Spherical Ti-6Ak-4V Powders Produced by Gas Atomization”, Key Engineering Materials, vol. 704, Aug. 2016, pp. 287-292. URL: https://www.scientific.net/KEM.704.287. |
Chikumba, S. et al., “High Entropy Alloys: Development and Applications”, 7th International Conference on Latest Trends in Engineering & Technology (ICLTET'2015), Nov. 26-27, 2015, Irene, Pretoria (South Africa), pp. 13-17. |
Dolbec, R., “Recycling Spherical Powders”, Presented at Titanium 2015, Orlando, FL, Oct. 2015, in 20 pages. |
He, J. Y. et al., “A precipitation-hardened high-entropy alloy with outstanding tensile properties”, Acta Materialia, 2016, vol. 102, pp. 187-196. |
Ivasishin, O. M. et al., “Innovative Process for Manufacturing Hydrogenated Titanium Powder for Solid State Production of R/M Titanium Alloy Components”, Titanium 2010, Oct. 3-6, 2010, in 27 pages. |
Kotlyarov, V. I. et al, “Production of Spherical Powders on the Basis of Group IV Metals for Additive Manufacturing”, Inorganic Materials: Applied Research, Pleiades Publishing, May 2017, vol. 8, No. 3, pp. 452-458. |
Laine, R. M. et al., “Making nanosized oxide powders from precursors by flame spray pyrolysis”, Key Engineering Materials, Jan. 1999, vol. 159-160, pp. 17-24. |
Lin, M., “Gas Quenching with Air Products' Rapid Gas Quenching Gas Mixture”, Air Products, Dec. 31, 2007, in 4 pages. URL: https://www.airproducts.co.uk/-/media/airproducts/files/en/330/330-07-085-us-gas-quenching-with-air-products-rapid-gas-quenching-gas-mixture.pdf. |
Muoto, C. et al., “Phase Homogeneity in Y2O3-MgO Nanocomposites Synthesized by Thermal Decomposition of Nitrate Precursors with Ammonium Acetate Additions”, Journal of the American Ceramic Society, 2011, vol. 94(12), pp. 4207-4217. |
Nyutu, E. et al., “Ultrasonic Nozzle Spray in Situ Mixing and Microwave-Assisted Preparation of Nanocrystalline Spinel Metal Oxides: Nickel Ferrite and Zinc Aluminate”, Journal of Physical Chemistry C, Feb. 1, 2008, vol. 112, No. 5, pp. 1407-1414. |
Popescu, G. et al., “New TIZrNbTaFe high entropy alloy used for medical applications”, IOP Conference Series: Materials Science and Engineering, Mod Tech 2018, Sep. 2018, vol. 400, in 9 pages. |
Reig, L. et al., “Microstructure and Mechanical Behavior of Porous Ti-6Al-4V Processed by Spherical Powder Sintering”, Materials, Oct. 23, 2013, vol. 6, pp. 4868-4878. |
Sheng, Y. et al., “Preparation of Spherical Tungsten Powder by RF Induction Plasma”, Rare Metal Materials and Engineering, Nov. 2011, vol. 40, No. 11, pp. 2033-2037. |
Sheng, Y. et al., “Preparation of Micro-spherical Titanium Powder by RF Plasma”, Rare Metal Materials and Engineering, Jun. 2013, vol. 42, No. 6, pp. 1291-1294. |
Suryanarayana, C., “Recent Developments in Mechanical Alloying”, Reviews on Advanced Materials Science, Aug. 2008, vol. 18(3), pp. 203-211. |
Van Laar, J. H. et al., “Spheroidisation of Iron Powder in a Microwave Plasma Reactor”, Journal of the Southern African Institute of Mining and Metallurgy, Oct. 2016, vol. 116, No. 10, pp. 941-946. |
Veith, M. et al., “Low temperature synthesis of nanocrystalline Y3Al5O12 (YAG) and Cedoped Y3Al5O12 via different sol-gel methods”, The Journal of Materials Chemistry, Jan. 1999, vol. 9, pp. 3069-3079. |
Wang, J. et al., “Preparation of Spherical Tungsten and Titanium Powders by RF Induction Plasma Processing”, Rare Metals, Jun. 2015 (published online May 31, 2014), vol. 34, No. 6, pp. 431-435. |
Yang, S. et al., “Preparation of Spherical Titanium Powders from Polygonal Titanium Hydride Powders by Radio Frequency Plasma Treatment”, Materials Transactions, Nov. 2013, vol. 54, No. 12, pp. 2313-2316. |
Zhang, K., Ph.D., “The Microstructure and Properties of Hipped Powder Ti Alloys”, a thesis submitted to the University of Birmingham, College of Engineering and Physical Sciences, Apr. 2009, in 65 pages. |
International Search Report and Written Opinion, re PCT Application No. PCT/US2016/067100, dated Mar. 22, 2017. |
International Search Report and Written Opinion, re PCT Application No. PCT/US2019/037956, dated Oct. 1, 2019. |
International Search Report and Written Opinion, re PCT Application No. PCT/US2019/037979, dated Aug. 22, 2019. |
International Search Report and Written Opinion, re PCT Application No. PCT/US2017/039049, dated Oct. 31, 2017. |
International Search Report and Written Opinion, re PCT Application No. PCT/IB2018/054523, dated Nov. 2, 2018. |
Dearmitt, C., “26. Functional Fillers for Plastics”, in Applied Plastics Engineering Handbook—Processing and Materials, ed., Myer Kutz, Elsevier, 2011, pp. 455-468. |
Gleiman, S. et al., “Melting and spheroidization of hexagonal boron nitride in a microwave-powered, atmospheric pressure nitrogen plasma”, Journal of Materials Science, Aug. 2002, vol. 37(16), pp. 3429 3440. |
Houmes et al., “Microwave Synthesis of Ternary Nitride Materials”, Journal of Solid State Chemistry, vol. 130, Issue 2, May 1997, pp. 266-271. |
International Preliminary Report on Patentability and Written Opinion, re PCT Application No. PCT/US2020/065536, dated Jun. 30, 2022. |
Majewksi, T., “Investigation of W—Re—Ni heavy alloys produced from plasma spheroidized powders”, Solid State Phenomena, Ma. 2013, vol. 199, pp. 448-453. |
Moldover, M. R. et al., “Measurement of the Universal Gas Constant R Using a Spherical Acoustic Resonator”, Physical Review Letters, Jan. 1988, vol. 60(4), pp. 249-252. |
Murugan et al. “Nanostructured a/β-tungsten by reduction of WO3 under microwave plasma”, Int. Journal of Refractory Metals and Hard Materials 29 (2011) 128-133. (Year: 2011). |
Nichols, F. A., “On the spheroidization of rod-shaped particles of finite length”, Journal of Materials Science, Jun. 1976, vol. 11, pp. 1077-1082. |
Park et al. “Preparation of spherical WTaMoNbV refractory high entropy alloy powder by inductively-coupled thermal plasma”, Materials Letters 255 (2019) 126513 (Year: 2019). |
Walter et al., “Microstructural and mechanical characterization of sol gel-derived Si—O—C glasses” Journal of the European Ceramic Society, vol. 22, Issue 13, Dec. 2002, pp. 2389-2400. |
Zhang, X. et al., “High thickness tungsten coating with low oxygen content prepared by air plasma spray”, Cailliao Gongcheng, 2014, vol. 5, pp. 23-28. |
Zhang, Y. S. et al., “Core-shell structured titanium-nitrogen alloys with high strength, high thermal stability and good plasticity”, Scientific Reports, Jan. 2017, vol. 7, in 8 pages. |
Ajayi, B. P. et al., “Atmospheric plasma spray pyrolysis of lithiated nickel-manganese-cobalt oxides for cathodes in lithium ion batteries”, Chemical Engineering Science, vol. 174, Sep. 14, 2017, pp. 302-310. |
Number | Date | Country | |
---|---|---|---|
20210187607 A1 | Jun 2021 | US |
Number | Date | Country | |
---|---|---|---|
62950778 | Dec 2019 | US |