The presently-disclosed subject matter relates to an extrusion apparatus. In particular, the presently-disclosed subject matter relates to an apparatus that can be used for indirect extrusion processes.
Metal extrusion generally refers to a process whereby a metal is formed into a particular shape by forcing the metal through an die. Extrusion is a metal press forming process that includes inserting a billet with a pre-defined length into a high temperature chamber and extruding the material by a movement of a ram or a die. Direct extrusion refers to an extrusion processes wherein the ram moves while the rest of the chamber and the die are stationary. Indirect extrusion refers to an extrusion processes wherein the die or the die and the chamber move together while the rest of the system remains stationary. The shape and length of metal billet are changed from an original state to a modified state depending on the shape of channel(s) in the die.
For instance, some known extrusion processes are capable of processing metal, such as aluminum and magnesium, into elongated shapes. Aluminum is desirable for certain applications given its low density and corrosion resistant properties. Consequently, extruded aluminum is commonly used in the aerospace, transportation, and other industries in which weight and/or corrosion resistance are required. Similarly, magnesium is another metal that is desirable for certain applications. Magnesium can be about 35% lighter than aluminum and about 75% lighter than steel. Magnesium also has favorable mechanical properties, including good strength, thermal conductivity, stiffness, and the like.
However, the development and installation of extrusion systems can be costly and time consuming. Among other things, this is due to the fact that there are no known systems that can be rapidly and efficiently reconfigured in order to analyze various different potential extruder designs. Therefore, it can be difficult to design extrusion systems without considerable investments of time, money, and resources.
Hence, there remains a need for extrusion systems and methods that are cost and time effective. Likewise, there remains a need for extrusion systems and methods that can facilitate the design and installation of new extrusion systems.
The presently-disclosed subject matter meets some or all of the above-identified needs, as will become evident to those of ordinary skill in the art after a study of information provided in this document.
This Summary describes several embodiments of the presently-disclosed subject matter, and in many cases lists variations and permutations of these embodiments. This Summary is merely exemplary of the numerous and varied embodiments. Mention of one or more representative features of a given embodiment is likewise exemplary. Such an embodiment can typically exist with or without the feature(s) mentioned; likewise, those features can be applied to other embodiments of the presently-disclosed subject matter, whether listed in this Summary or not. To avoid excessive repetition, this Summary does not list or suggest all possible combinations of such features.
The presently-disclosed subject matter includes an apparatus for extruding materials. In some instances the material is selected from a metal, a polymer, and combinations thereof. In some embodiments the apparatus comprises a chamber that includes an opening that faces at least a downstream side of the chamber, the opening having a size corresponding to the material in an original state, a die downstream of the chamber that is slideably received by the opening of the chamber, the die including a channel that is substantially in fluid communication with the opening of the chamber, and a base portion that includes a fixture, the fixture being annular and configured to couple to a downstream side of the die. In some embodiments the base portion further comprises a weld chamber that is in fluid communication with the channel of the die, wherein an upstream side of the weld chamber is configured to couple to a downstream side of the fixture. In some embodiments the weld chamber includes one or more windows on side thereof that communicate between an exterior side and an interior side of the weld chamber. In further embodiments the fixture is integral with the weld chamber.
In some embodiments the die comprises a splitter, the splitter including one or more webs that define two or more channels. The splitter can be disposed on an upstream side of the die. In some embodiments the splitter includes a center obstruction and a peripheral ring, wherein the one or more webs radially extend from the center obstruction to the peripheral ring.
In some embodiments an upstream side of the die includes a surface that slopes in the direction of the channel.
In some embodiments the chamber is comprised of two or more separate elements. For example, a chamber can be comprised of a first housing and a second housing, wherein the first housing is upstream of the second housing. The chamber can further comprise a plug configured to be received at least by the first housing, wherein a downstream side of the plug can optionally include an indent (cavity) that corresponds in shape to the material. Furthermore, in some embodiments the chamber also includes a sleeve that is annular, an exterior surface of the sleeve corresponding to an interior surface of the second housing, and an interior surface of the sleeve defining the opening of the chamber.
In some embodiments the apparatus for extruding a material comprises a chamber that includes an opening, which faces at least a downstream side of the chamber, for receiving the material in an original state. In some embodiments the chamber includes a first housing and a second housing that is disposed downstream of the first chamber, a plug configured to be received at least by the first housing, a sleeve that is annular and configured to move axially at least within the second chamber, and a clamp for coupling the first chamber and the second chamber. The embodied apparatus can also comprise a die that is downstream and slideably received by the opening of the chamber, a base portion that includes a fixture, the fixture being annular and configured to couple to a downstream side of the die, and a channel that continuously extends from the opening of the chamber and through the die and the fixture.
The presently-disclosed subject matter also provides methods for extruding a material. Exemplary methods for extruding a material can comprise providing an apparatus that includes a chamber comprising an opening faces at least a downstream side of the chamber, the opening having a size corresponding to the material in an original state, a die that is downstream of the chamber and slideably received by the opening of the chamber, the die including a channel that is in fluid communication with the opening of the chamber, and a base portion that includes a fixture, the fixture being annular and configured to couple to a downstream side of the die; placing a material in an original state within the opening of the chamber and upstream of the die; applying a force to an upstream side of the chamber to thereby push the material through the channel of the die; and collecting the material in a modified state downstream of the fixture.
In some embodiments the methods further comprise, before the applying step, thermally soaking the material in the original state to a soaking temperature corresponding to about 50% to about 99% of a melting temperature of the material, and in some embodiments to a soaking temperature corresponding to about 70% to about 90% of the melting temperature of the material. In some embodiments the thermal soaking step can be about 0.5 hours to about 3.0 hours in duration.
In some embodiments a longitudinal axis of the apparatus is oriented in an vertical position during the extrusion process.
The details of one or more embodiments of the presently-disclosed subject matter are set forth in this document. Modifications to embodiments described in this document, and other embodiments, will be evident to those of ordinary skill in the art after a study of the information provided in this document. The information provided in this document, and particularly the specific details of the described exemplary embodiments, is provided primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom. In case of conflict, the specification of this document, including definitions, will control.
The presently-disclosed subject matter includes apparatuses for extruding materials. In some embodiments the materials include polymers or metals, such as lightweight metals or alloys thereof. In some embodiments the metals are selected from aluminum, magnesium, and the like. In some instances the extruding apparatuses permit quick and efficient interchangeability of apparatus' configuration, thereby permitting relatively inexpensive and rapid testing of different extrusion configurations.
Turning now to the Figures, various view of exemplary embodiments of extrusion apparatuses are shown.
The apparatus 1 shown in
In the embodied apparatus 1 both the first housing 5 and the second housing 6 are annular. A plug 11 is provided within at least the first housing 5 so that a top of the chamber 3 forms a flat surface.
A die is provided 20 downstream of the chamber 3. The die 20 is configured to be slideably received by an opening 4 provided on a downstream side of the chamber 3. More specifically, in embodiments wherein the second housing 6 is annular, and the interior of the second housing 6 defines the opening 4 that can slideably receive the die 20.
A base portion is provided 40 downstream of the die 20. The base portion is comprised of a fixture 31. An upstream side of the fixture 31 includes a die seat 33 that can receive a downstream side of the die 20. Thus, by placing the die 20 within the die seat 33, the die 20 and the fixture 31 can couple and form one continuous element. As shown in other figures provided herein, in some embodiments the die seat 33 includes an indent that is provided on an upstream side of the fixture 31 and that corresponds in shape to the downstream side of the die 20. For instance,
Further still, the exemplary apparatus 1 includes an optional weld chamber 41 that forms a portion of the base portion 40. The weld chamber 41 can provide an area for an extrudate to collect, and in some instances provides space in a furnace to allow an extruded product to exit the die 20 and be cut into desired dimensions. Conditions within the weld chamber 41 can also be adjusted by a user to expose the extrudate to particular temperatures, gasses, and the like. Windows 43 can be provided on a side of the weld chamber 41 and can permit observation and/or collection of the extrudate, wherein the windows 43 define openings that communicate between an exterior side and an interior side of the weld chamber 41.
Looking now to
Chambers 3 that are comprised of a plurality of elements can facilitate disassembly and modification of the extrusion apparatus 1. For instance, if a surface of the sleeve 15 is compromised, the sleeve 15 can be interchanged without requiring replacement of the entire chamber 3. Sleeves 15 of different sizes can also be provided for different sized billets 50 so that a single apparatus 50 may be used to extrude different sized billets 50. Furthermore, in order to avoid welding and alloying of the different elements, the sleeve 15 material can be selected so that it differs from a material of the second chamber 6 and a material of the billet 50.
Likewise, embodiments of multi-component extrusion apparatuses 1 having a clamp 9 can be disassembled by opening the clamp 9. Once disassembled, one can configure the apparatus 1 by interchanging the components of the apparatus 1. One can thus modify or interchange the die 20 and/or extrusion apparatus 1 configuration so that the material being extruded exits the die 20 so as to meet a specific profile of a product. Since the interchangeability can be relatively efficient and quick, embodiments of the present extrusion apparatus 1 permit the die 20 to be redesigned and reproduced without requiring a new fixture assembly.
Embodiments of the present apparatuses also have the benefit of being capable of being configured as laboratory-scale or small-scale systems. Such apparatuses and systems can provide a novel set of data to create process-structure-property relationships, including for lightweight alloys such as aluminum and magnesium, under extremely large deformation at elevated temperature conditions. Thus, no matter the scale of the apparatuses and systems, the presently-disclosed subject matter can provide apparatuses and systems for experimental extrusion configurations that characterize certain materials, processes, extruder assemblies, or the like. This can be particularly so for small or laboratory-scale implantations, which can be more cost and time effective to run and reconfigure. Furthermore, even if small or laboratory scale implementations are utilized, the processing parameters, process structure, and other data obtained for such systems and methods can be transferred to scale-up operations for industrial extrusion systems and methods.
Those of ordinary skill will appreciate that a chamber 3 can be comprised of fewer or more elements than those depicted in
In
A cross-sectional view of the embodied apparatus 1 is shown in
In this regard, and looking now to
As described above, the downstream side of the die 20 can be coupled to the fixture via a die seat 33.
The design of the dies 20 is not particularly limited, and may be altered in various embodiments. Indeed, exemplary dies 20 can have one or more bearings 22 of various shapes and sizes that yield desired extrudates. In some embodiments the dies comprise two or more bearings 22, and therefore the extrudate includes two or more streams of the material flowing from the die 20. Dies are not limited to dies that produce extruded product having a circular or oval outer profile. Instead, dies can be configured so that the extruded product can be flat, square, triangular, or another irregular shape or pattern. It will be appreciated by those in the art that dies can be configured to have a multitude of shapes and dimensions.
For example,
Specifically,
The number of webs 27 and channels 23 on a splitter die 20 are not particularly limited. In some embodiments a splitter die 20 can be configured to have about 2, 3, 4, 5, 6, 7, 8, 9, 10, or more webs and/or channels. For instance,
As shown in
The splitter die 20 of
The presently-disclosed subject matter also includes methods for extruding materials. While embodiments of the apparatuses described herein are intended for indirect extrusion, those of ordinary skill in the art will appreciate that the apparatuses or variations thereof can also be used for direct extrusion processes.
In some embodiments the method of extrusion comprises providing an embodiment of the apparatuses described herein, the apparatus comprising a chamber that includes an opening that faces at least a downstream side of the chamber, the opening having a size corresponding to the material in an original state, a die downstream of the chamber that is slideably received by the opening of the chamber, the die including a channel that is in fluid communication with the opening of the chamber, and a base portion that includes a fixture, the fixture being annular and configured to couple to a downstream side of the die. Embodiments of methods for extruding a material further comprise placing a material in an original state within the opening and upstream of the die, applying a force to an upstream side of the chamber to thereby push the material through the channel of the die, and collecting the material in a modified state downstream of the fixture. Furthermore, in some embodiments a step of lubricating the apparatus is provided. The lubricant can be used to facilitate the extrusion step, and exemplary lubricants include graphite or a graphite paste.
The material being extruded will generally conform to the shape of the apparatus, and particularly the die, so that the extrudate exiting the apparatus has a profile that corresponds to a configuration of the die. The resulting extruded product can comprise a solid and/or hollow profile as well as desirable shapes, thicknesses, and mechanical properties. In some embodiments the extruded material is a lightweight metal or metal alloy, including aluminum, magnesium, other metals, or alloys thereof. In other embodiments the material includes one or more polymers. The present extrusion methods can be implemented to produce lightweight products.
In some embodiments methods for extruding a material further comprise a thermal soaking step. The thermal soak step commences prior to at least the step of applying a force to an upstream side of the chamber. The thermal soaking step can heat a bulk material to a temperature that is below the melting point of the particular material. For example, thermal soaking can involve heating the bulk material in a furnace near the extrusion apparatus and/or heating the material in its original state after it has been placed within an extrusion apparatus. For a lightweight material, the soaking temperature can be about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% of the bulk material's melting temperature. In some embodiments the soaking temperature corresponds to about 70% to about 90% of the melting temperature of the material. In certain embodiments the thermal soaking step can comprise heating a bulk material to about 100° C., 200° C., 300° C., 400° C., 500° C., 600° C., 700° C., 800° C., 900° C., 1000° C., 1100° C., 1200° C., 1300° C., 1400° C., 1500° C., or any other suitable temperature.
The duration of the thermal soaking step is not particularly limited. In some embodiments thermal soaking is carried out for a time sufficient to achieve a uniform temperature throughout the bulk material and/or the extrusion apparatus. In this regard, in some embodiments thermal soaking is performed for about 0.5 hours, 1.0 hours, 1.5 hours, 2.0 hours, 2.5 hours, or 3.0 hours. Of course, the time that thermal soaking is performed can vary depending on the temperature of the thermal soaking, the desired final temperature, the material being heated, and the dimension of the material being extruded. Thermal soaking can also be performed for a period of time after the temperature of the material being extruded has equilibrated and attained a uniform temperature.
Furthermore, to maintain the integrity of the material prior to extrusion, thermal soaking of lightweight alloys, such as magnesium alloy, can be performed under a noble gas environment and at a particular temperature range that will allow the material to maintain fluidity for the subsequent extrusion. This can minimize the possibility of oxidation happening under high temperature. This can also prevent the material from disintegrating before extrusion due to pre-matured cracking and/or surface cracking during extrusion.
The presently-disclosed subject matter is further illustrated by the following specific but non-limiting examples. The examples may include compilations of data that are representative of data gathered at various times during the course of development and experimentations related to the presently-disclosed subject matter.
This Example describes extrusion processes conducted using embodiments of the presently-disclosed apparatuses. Among other things, this Example characterizes different thermal soaking temperatures during the thermal soaking step and during extrusion.
To characterize the extrudate, thermocouples were introduced into the apparatus. Specifically, three thermocouple holes were drilled into the second (bottom) housing that receives the sleeve. A first thermocouple (TC1) was installed into a hole drilled in the second housing at a midpoint along its longitudinal length. A second thermocouple (TC2) was installed in a hole drilled towards the upstream side of the second housing and on an area that would be covered by a clamp.
Two additional thermocouples (TC3 and TC4) were also added to the die to obtain data of the temperature history at different points in the billet-extrudate during the extrusion procedure.
Next, an aluminum 1100 material was heated and then extruded through the apparatus. The bulk material was heated and held to the testing temperature for a period of time.
This Example describes and characterizes extrusion processes conducted using the apparatus described in Example 1.
Procedures were conducted to extrude lightweight materials such as aluminum and magnesium, and also to produce weld seams using the above-described two-porthole splitter. For example, 1100F Aluminum and Mg alloys of AM30 and AZ61 were extruded. For instance,
This Example describes and characterizes extrusion of material with a splitter die. Specifically, the solid-state bonding process that occurs in splitter dies of hollow Mg extrusions will be examined by using a splitter placed between the chamber and the die (lower die portion). The splitter includes one web that splits the flow into two channels. The rear end of the web has a butt-ended shape that is apart 1/16″ from the bearing. The extrudate should include an elongated profile with an extrusion seam in the middle.
Initial extrusion procedures were conducted using the splitter and 1100F Aluminum. Processing conditions were 300° C., 5 mm/min, and extrusion ratio of 25.
Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently-disclosed subject matter, representative methods, devices, and materials are described herein.
Following long-standing patent law convention, the terms “a”, “an”, and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to “a die” includes a plurality of such dies, and so forth.
The terms “comprising”, “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Unless otherwise indicated, all numbers used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in this specification and claims are approximations that can vary depending upon the desired properties sought to be obtained by the presently-disclosed subject matter. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.
As used herein, the term “about,” when referring to a value or to an amount of mass, weight, time, volume, concentration or percentage is meant to encompass variations of in some embodiments ±50%, in some embodiments ±40%, in some embodiments ±30%, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1% from the specified amount, as such variations are appropriate to perform the disclosed method.
1—extrusion apparatus
3—chamber
4—opening
5—first (top) housing
6—second (bottom) housing
7—first groove
8—second groove
9—clamp
10—screw
11—plug
13—indent
15—sleeve
20—die
21—upstream side of die
22—bearing
23—channel
25—upper die portion
26—center obstruction
27—web
28—peripheral ring
29—lower die portion
31—fixture
33—die seat
40—base portion
41—weld chamber
43—window
50—billet
This application claims priority from U.S. Provisional Patent Application No. 61/866,963, filed Aug. 16, 2014, the entire disclosure of which is incorporated herein by this reference.
This invention was made with government support under Grant Number DE-FC26-06NT42755 awarded by the U.S. Department of Energy. The government has certain rights in the invention.
Number | Date | Country | |
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61866963 | Aug 2013 | US |