Patent Application
20230055545
The present disclosure generally pertains to irradiation devices for irradiating powder material to additively manufacture three-dimensional objects, such as irradiation devices used in powder bed fusion processes.
Three dimensional objects may be additively manufactured using a powder bed fusion process in which an energy beam generated by an irradiation device is directed onto a powder bed to melt and/or sinter sequential layers of powder material. The properties of the three dimensional object formed by melting and/or fusing the powder material may depend at least in part on one or more characteristics of the energy beam provided by the irradiation device and/or on the irradiation sequence performed by the irradiation device. Accordingly, it would be welcomed in the art to provide improved additive manufacturing systems and machines, including improved energy beam systems and/or irradiation devices, as well as improved irradiation sequences that may be performed by such energy beam systems and/or irradiation devices.
A full and enabling disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended Figures, in which:
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present disclosure.
Reference now will be made in detail to exemplary embodiments of the presently disclosed subject matter, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation and should not be interpreted as limiting the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope of the present disclosure. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents.
It is understood that terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows. It is also understood that terms such as “top”, “bottom”, “outward”, “inward”, and the like are words of convenience and are not to be construed as limiting terms. As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “a” and “an” do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “substantially,” and “approximately,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and/or systems. For example, the approximating language may refer to being within a 10 percent margin.
Here and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.
The present disclosure generally provides additive manufacturing machines and methods of additively manufacturing three-dimensional objects. Exemplary additive manufacturing machines may utilize irradiation devices that include a plurality of laser diode arrays configured for a powder bed fusion process. The plurality of laser diode arrays may be configured to work in concert with one another to irradiate a powder bed with a linear or curvilinear pattern of beam spots. At least some of the beam spots from respective ones of the plurality of laser diode arrays may become incident upon the powder bed in an alternating pattern or sequence. The alternating pattern or sequence of beam spots may allow for an effective pitch length that is smaller than the effective pitch length of the laser diode arrays. The smaller effective pitch may provide a pattern of beam spots that are sufficiently close to one another to avoid potential gaps between adjacent melt tracks.
The alternating pattern or sequence may allow for linear or curvilinear irradiation patterns while providing improved control of heat input and melt pool geometry. For example, build points that are irradiated by a linear or curvilinear patterns of beam spots may have a tendency to thermally interact with one another as heat conduction from adjacent build points propagates across the powder bed. These interactions may introduce variability in the localized energy density of respective build points, which variability can lead to variable melt pool size and geometry. For example, heat conduction from adjacent build points may cause heat conduction gradient transverse to the adjacent build points, which may lead to an ovalized and/or irregularly shaped melt pool. The nature and extent of the variability may depend on the distance between adjacent beam spots, the power density or intensity of adjacent beam spots, and/or the proportion of the local area of the powder bed being irradiated, among other things. The presently disclosed alternating pattern or sequence of beam spots may reduce the tendency for adjacent build points to introduce variability with respect to one another, which may allow a more uniform power density and/or improved controllability of the power density at the respective build points. The improved uniformity and/or controllability may provide for improved build quality and/or uniformity. Additionally, or in the alternative, the presently disclosed alternating pattern or sequence of beam spots may allow for increased processing speeds, for example, without sacrificing build quality and/or uniformity. Advantageously, such increased processing speeds may further reduce the tendency for thermal interactions from adjacent build points, which may lead to even further improvements in build quality and/or uniformity.
In addition to the presently disclosed irradiation devices having a plurality of laser diode arrays that provide an alternating pattern or sequence of beam spots, exemplary irradiation devices may include laser diode arrays that emit energy beam segments with a relatively lower intensity and/or power density in comparison to existing irradiation devices and/or laser diode arrays typically utilized in powder bed fusion processes. For example, an irradiation device may include a plurality of laser diode arrays that emit a plurality of energy beams that impart a power density and/or intensity to the build plane commensurate with a conduction irradiation regime. As used herein, the term “conduction irradiation” or “conduction irradiation regime” refers to an irradiation regime in a powder bed fusion process in which heat is transferred into the powder bed predominately through heat conduction such that the thermal conductivity of the powder material is the limiting factor for the depth of the melt pool. The temperature of the melt pool with conduction irradiation generally remains below the vaporization temperature of the powder material. With a conduction irradiation regime, the width of a melt pool is typically much greater than the depth of the melt pool. A melt pool resulting from conduction irradiation may have an aspect ratio of less than about 1.0 (width/depth), such as from about 0.1 to about 1.0, such as from about 0.1 to about 0.5, or such as from about 0.5 to about 1.0. A melt pool resulting from conduction irradiation may have a depth of from about 10 micrometers (μm) to about 250 μm, such as from about 10 μm to about 50 μm, such as from about 50 μm to about 100 μm, or such as from about 100 μm to about 250 μm.
Conduction irradiation may be differentiated from penetration irradiation. As used herein, the term “penetration irradiation” or “penetration irradiation regime” refers to an irradiation regime in a powder bed fusion process in which the temperature of the melt pool exceeds the vaporization temperature of the powder material to an extent that the energy beams penetrate into a vapor capillary formed by expanding gasses releasing from the vaporizing power material. With penetration irradiation, the temperature of the melt pool adjacent to the vapor capillary generally exceeds the vaporization temperature of the powder material. With a penetration irradiation regime, the width of a melt pool is typically much smaller than the depth of the melt pool. A melt pool resulting from penetration irradiation may have an aspect ratio of greater than about 1.0 (width/depth), such as from about 1.0 to about 18.0, such as from about 1.0 to about 5.0, such as from about 5.0 to about 10.0, or such as from about 10.0 to about 18.0. A melt pool resulting from penetration irradiation may have a depth of from about 100 μm to about 1 millimeter (mm), such as from about 100 μm to about 250 μm, such as from about 250 μm to about 500 μm, or such as from about 500 μm to about 800 μm.
An irradiation device that includes a plurality of laser diode arrays configured and arranged in accordance with the present disclosure may be advantageously utilized with a conduction irradiation regime. The relatively lower intensity and/or power density associated with conduction irradiation may allow for a plurality of laser diode arrays to be configured and arranged to provide an alternating pattern of beam spots with a relatively low pitch between respective beam spots, thereby allowing for increased resolution when irradiating the powder bed without causing excessive thermal interactions between adjacent beam spots. The increased resolution realized by the present disclosure may be utilized to facilitate sophisticated irradiation strategies that provide for improved temperature control and/or improved material properties of three dimensional objects formed during an additive manufacturing process. Additionally, or in the alternative, the increased resolution realized by the present disclosure may be utilized to produce three dimensional objects that have smaller features, improved surface properties, and/or greater dimensional tolerances.
A plurality of energy beams respectively corresponding to a plurality of laser diodes from the laser diode arrays may be directed onto the build plane, providing a plurality of beam spots in the form of an alternating pattern, such as an alternating pattern of beam spots with a linear or curvilinear arrangement. The linear or curvilinear arrangement of beam spots may be scanned across the powder bed while respective laser diodes may be modulated according to irradiation instructions. The irradiation instructions may specify which build points on the powder bed are intended to receive irradiation from a beam spot corresponding to a respective one or more laser diodes from the plurality of laser diode arrays. The powder bed can be irradiated with good resolution while the beam spots are modulated by the respective laser diodes. With a conduction irradiation regime, heat transfer from adjacent beam spots may be limited by the thermal conductivity of the powder material, and as such, the melt pool corresponding to respective beam spots can be substantially confined to specified build points of the powder bed. In some embodiments, the presently disclosed additive manufacturing machines may allow for a powder bed to be irradiated with a resolution that approaches or corresponds to a cross-sectional width of a beam spot.
As described herein, the presently disclosed subject matter involves the use of additive manufacturing machines or systems. As used herein, the term “additive manufacturing” refers generally to manufacturing technology in which components are manufactured in a piece-by-piece or layer-by-layer manner. An exemplary additive manufacturing machine may be configured to utilize any suitable additive manufacturing technology. The additive manufacturing machine may utilize an additive manufacturing technology that includes a powder bed fusion (PBF) technology, such as a direct metal laser melting (DMLM) technology, a selective laser melting (SLM) technology, a directed metal laser sintering (DMLS) technology, or a selective laser sintering (SLS) technology. In an exemplary PBF technology, thin layers of powder material are sequentially applied to a build plane and then selectively melted or fused to one another in a layer-by-layer manner to form one or more three-dimensional objects. Additively manufactured objects are generally monolithic in nature and may have a variety of integral sub-components.
Additionally or alternatively suitable additive manufacturing technologies may include, for example, Fused Deposition Modeling (FDM) technology, Direct Energy Deposition (DED) technology, Laser Engineered Net Shaping (LENS) technology, Laser Net Shape Manufacturing (LNSM) technology, Direct Metal Deposition (DMD) technology, Digital Light Processing (DLP) technology, Vat Polymerization (VP) technology, Stereolithography (SLA) technology, and other additive manufacturing technologies that utilize an energy beam or other energy source to solidify an additive manufacturing material such as a powder material. In fact, any suitable additive manufacturing modality may be utilized with the presently disclosed the subject matter.
Additive manufacturing technology may generally be described as fabrication of objects by building objects point-by-point, line-by-line, or layer-by-layer, typically in a vertical direction. Other methods of fabrication are contemplated and within the scope of the present disclosure. For example, although the discussion herein refers to the addition of material to form successive layers, the presently disclosed subject matter may be practiced with any additive manufacturing technology or other manufacturing technology, including layer-additive processes, layer-subtractive processes, or hybrid processes.
The additive manufacturing processes described herein may be used for forming components using any suitable material. For example, the material may be metal, ceramic, polymer, epoxy, photopolymer resin, plastic, concrete, or any other suitable material that may be in solid, liquid, powder, sheet material, wire, or any other suitable form, or combinations thereof. Exemplary materials may include metals, polymers, or ceramics, as well as combinations thereof. Additionally, or in the alternative, exemplary materials may include metals, ceramics, or binders, as well as combinations thereof. Exemplary ceramics may include ultra-high-temperature ceramics, and/or precursors for ultra-high-temperature ceramics, such as polymeric precursors. Each successive layer of powder material may be, for example, between about 10 μm and 200 μm, although the thickness may be determined based on any number of parameters and may be any suitable size.
As used herein, the term “build plane” refers to a plane defined by a surface upon which an energy beam impinges during an additive manufacturing process. Generally, the surface of a powder bed defines the build plane. During irradiation of a respective layer of the powder bed, a previously irradiated portion of the respective layer may define a portion of the build plane, and/or prior to distributing powder material across a build module, a build plate that supports the powder bed generally defines the build plane.
It is understood that terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows, and “downstream” refers to the direction to which the fluid flows. It is also understood that terms such as “top”, “bottom”, “outward”, “inward”, and the like are words of convenience and are not to be construed as limiting terms. As used herein, the terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “a” and “an” do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “substantially,” and “approximately,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and/or systems. For example, the approximating language may refer to being within a 10 percent margin.
Here and throughout the specification and claims, range limitations are combined and interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.
The presently disclosed subject matter will now be described in further detail.
As shown, the one or more additive manufacturing machines 102 may include a control system 104. The control system 104 may be included as part of the additive manufacturing machine 102 or the control system 104 may be associated with the additive manufacturing machine 102. The control system 104 may include componentry integrated as part of the additive manufacturing machine 102 and/or componentry that is provided separately from the additive manufacturing machine 102. Various componentry of the control system 104 may be communicatively coupled to various componentry of the additive manufacturing machine 102.
The control system 104 may be communicatively coupled with a management system 106 and/or a user interface 108. The management system 106 may be configured to interact with the control system 104 in connection with enterprise-level operations pertaining to the additive manufacturing system 100. Such enterprise level operations may include transmitting data from the management system 106 to the control system 104 and/or transmitting data from the control system 104 to the management system 106. The user interface 108 may include one or more user input/output devices to allow a user to interact with the additive manufacturing system 100.
As shown, for example, in
As shown, for example, in
Typically, with a DMLM, EBM, or SLM system, the powder material 120 is fully melted, with respective layers being melted or re-melted with respective passes of the energy beams. With DMLS or SLS systems, typically the layers of powder material 120 are sintered, fusing particles of powder material 120 to one another generally without reaching the melting point of the powder material 120. The energy beam system 134 may include componentry integrated as part of the additive manufacturing machine 102 and/or componentry that is provided separately from the additive manufacturing machine 102.
The energy beam system 134 may include one or more irradiation devices 142 configured to generate a plurality of energy beams 144 and to direct the energy beams 144 upon the build plane 130. As shown, for example, in
The plurality of energy beams 144 may become incident directly upon the build plane 130, for example, after passing through one or more optical elements 136 and/or a window 137 of the energy beam system 134. Additionally, or in the alternative, an irradiation device 142 may include a scanner configured to direct the plurality of energy beams 144 onto the powder bed 138. An exemplary scanner may include a galvo scanner, an electro-optic modulator, an acousto-optic modulator, a piezo-driven mirror, or the like. To irradiate a layer of the powder bed 138, the one or more irradiation devices 142 respectively direct the plurality of energy beams 144 across the respective portions of the build plane 130 to melt or fuse the portions of the powder material 120 that are to become part of the object 114. The sequential layers of the powder bed 138 are melted or fused to one another to additively manufacture the object 114. As sequential layers of the powder bed 138 are melted or fused to one another, a build piston 146 gradually moves the build platform 132 to make room for sequential layers of powder material 120. As the build piston 146 gradually lowers and sequential layers of powdered material 120 are applied across the build plane 130, the next sequential layer of powder material 120 defines the surface of the powder bed 138 coinciding with the build plane 130. Sequential layers of the powder bed 138 may be selectively melted or fused until a completed object 114 has been additively manufactured.
Still referring to
An energy beam system 134 and/or an imaging system 148 may include one or more detection devices. The one or more detection devices may be configured to determine one or more parameters of an energy beam system 134, such as one or more parameters associated with irradiating the sequential layers of the powder bed 138 based at least in part on an assessment beam detected by the imaging system 148. One or more parameters associated with irradiating the sequential layers of the powder bed 138 may include irradiation parameters and/or object parameters, such as melt pool monitoring parameters. The one or more parameters determined by the imaging system 148 may be utilized, for example, by the control system 104, to control one or more operations of the additive manufacturing machine 102 and/or of the additive manufacturing system 100. The one or more detection devices may be configured to obtain assessment data of the build plane 130 from a respective assessment beam. An exemplary detection device may include a camera, an image sensor, a photo diode assembly, or the like. For example, a detection device may include charge-coupled device (e.g., a CCD sensor), an active-pixel sensor (e.g., a CMOS sensor), a quanta image device (e.g., a QIS sensor), or the like. A detection device may additionally include a lens assembly configured to focus an assessment beam along a beam path to the detection device. An imaging system 148 may include one or more imaging optical elements (not shown), such as mirrors, beam splitters, lenses, and the like, configured to direct an assessment beam to a corresponding detection device.
In addition, or in the alternative to determining parameters associated with irradiation the sequential layers of the powder bed 138, the imaging system 148 may be configured to perform one or more calibration operations associated with an additive manufacturing machine 102, such as a calibration operation associated with the energy beam system 134, one or more irradiation devices 142 or components thereof, and/or the imaging system 148 or components thereof. The imaging system 148 may be configured to project an assessment beam and to detect a portion of the assessment beam reflected from the build plane 130. The assessment beam may be projected by an irradiation device 142 and/or a separate beam source associated with the imaging system 148. Additionally, and/or in the alternative, the imaging system 148 may be configured to detect an assessment beam that includes radiation emitted from the build plane 130, such as radiation from an energy beam 144 reflected from the powder bed 138 and/or radiation emitted from a melt pool in the powder bed 138 generated by an energy beam 144 and/or radiation emitted from a portion of the powder bed 138 adjacent to the melt pool. The imaging system 148 may include componentry integrated as part of the additive manufacturing machine 102 and/or componentry that is provided separately from the additive manufacturing machine 102. For example, the imaging system 148 may include componentry integrated as part of the energy beam system 134. Additionally, or in the alternative, the imaging system 148 may include separate componentry, such as in the form of an assembly, that can be installed as part of the energy beam system 134 and/or as part of the additive manufacturing machine 102.
Still referring to
The control commands may be provided, for example, to carry out operations of the one or more energy beam system 134 and/or of the additive manufacturing machine 102 in accordance with the present disclosure. The positioning system 150 may include one or more gantry elements 152 configured to move the energy beam system 134 and/or one or more components thereof across the powder bed 138. Respective gantry elements 152 may be configured to move the energy beam system 134 and/or one or more components thereof in one or more directions, such as an X-direction, a Y-direction, and/or a Z-direction. In some embodiments, the positioning system 150 may be coupled to a housing assembly 154 that contains one or more components of the energy beam system 134, such as one or more irradiation devices 142 and or one or more imaging systems 148. The housing assembly 154 may be coupled to one or more gantry elements 152 by one or more gantry mounts 156. The positioning system 150 may include a drive motor 158 configured to move the housing assembly 154 and/or the one or more components the energy beam system 134 according to instructions for the control system 104. The positioning system 150 may include componentry typically associated with a gantry system, such as stepper motors, drive elements, carriages, and so forth.
The energy beam system 134 may be positioned at any suitable location within the process chamber 140. Additionally, or in the alternative, the energy beam system 134 may be coupled to a perimeter wall of the process chamber 140. In some embodiments, as shown, for example, in
Referring now to
As shown in
As shown in
As shown in
The one or more build vessels 212 may be operably coupled to a build vessel-positioning system 212 in addition to, or in the alternative to, one or more build units 200 operably coupled to a build unit-positioning system 208. For example, an additive manufacturing machine 102 may include a build vessel-positioning system 212 and one or more stationary build units 200. Additionally, or in the alternative, an additive manufacturing machine 102 may include a build vessel-positioning system 212 and a build unit-positioning system 208. The build vessel-positioning system 212 may be configured to move a build vessel 202 in one or more directions, and the build vessel-positioning system 212 may be configured to move a build vessel 202 in one or more directions. For example, the build vessel-positioning system 212 may be configured to move a build vessel 202 in an X-direction and/or a Y-direction. Additionally, or in the alternative, the build unit-positioning system 208 may be configured to move a build unit 200 in a Z-direction.
A build vessel-positioning system 212 may be configured to move a build vessel 202 horizontally while one or more build units 200 selectively irradiate portions of the powder material 120 in the build vessel 202. For example, the build vessel-positioning system 212 may be configured to move a build vessel 202 in accordance with an X-Y coordinate system. Additionally, or in the alternative, a build unit-positioning system 208 may be configured to move a build unit 200 horizontally while the build unit 200 selectively irradiates portions of the powder material 120 in the build vessel 202. For example, the build vessel-positioning system 212 may be configured to move a build vessel 202 in accordance with an X-Y coordinate system. A vertical position of the one or more build units 200 and/or the build vessel 202 may be augmented in connection with the addition of sequential layers of powder material 120 to the build vessel 202 and selective irradiation of the respective layers of powder material 120 in the build vessel 202. The build vessel-positioning system 212 may be configured to sequentially move the build vessel 202 vertically to provide room for the next sequential layer of powder material 120 to be added to the build vessel 202. Additionally, or in the alternative, the build unit-positioning system 208 may be configured to sequentially move a build unit 200 vertically to provide room for the next sequential layer of powder material 120 to be added to the build vessel 202. Movements of the build unit 200 and/or the build vessel 202 may be carried out before, during, or after, irradiating a sequential layer of powder material 120.
Referring now to
The irradiation device may include a beam conditioning assembly 306. The beam conditioning assembly 306 may be disposed downstream from the beam generation device 300. The beam conditioning assembly 306 may include a conditioning housing 308 configured to support one or more optical elements configured to focus and/or otherwise condition the energy beams 144 emitted by the diode emitters 304. In some embodiments, the beam conditioning assembly 306 may include one or more collimating lenses. For example, as shown, the beam conditioning assembly 306 may include a fast-axis collimating lens 310 and/or a slow-axis collimating lens 312. The fast-axis collimating lens 310 and the slow-axis collimating lens 312 may be provided as separate optical elements or respective portions of a common optical element. In some embodiments, the fast-axis collimating lens 310 and/or the slow-axis collimating lens 312 may be configured as a microlens array.
In some embodiments, the beam conditioning assembly 306 may include a beam homogenizer 314, for example, disposed downstream from the one or more collimating lenses. An exemplary beam homogenizer 314 may include one or more microlens arrays in front of a condenser lens. The beam homogenizer 314 may be configured to provide a uniform power distribution with respect to a cross-sectional profile of respective ones of the plurality of energy beams 144 and/or with respect to the plurality of energy beams 144 as a group. For example, an energy beam 144 may have a Gaussian power distribution as emitted by a laser diode and/or after having been collimated. In some embodiments, the beam homogenizer 314 may be configured to provide a top-hat power distribution. Additionally, or in the alternative, the beam homogenizer 314 may be configured to provide a plurality of energy beams 144 that have a substantially uniform intensity and/or powder level. Additionally, or in the alternative, the beam homogenizer may be configured to correct smile error across a plurality of energy beams 144 collimated by one or more collimating lenses of the beam conditioning assembly 306. For example, the beam homogenizer may include individually addressable optical elements, such as lenses or mirrors, configured to adjust respective ones of the plurality energy beams 144 to provide a plurality of energy beams 144 that have a coplanar orientation and/or a common optical plane.
An irradiation device 142 may include a beam focusing assembly 316 disposed downstream from the beam conditioning assembly 306. The beam focusing assembly 316 may include a focusing housing 318 configured to support one or more focusing lenses 320. An exemplary focusing lens 320 may include a cylindrical plano-convex lens. In some embodiments, a beam focusing assembly 316 may include a fast-axis focusing lens, such as a fast-axis plano-convex lens. Additionally, or in the alternative, a beam focusing assembly 316 may include a slow-axis focusing lens, such as a slow-axis plano-convex lens.
The irradiation device 142 may include any one or more other optical elements that may be suitable for the particular embodiment. For example, the irradiation device 142 may include one or more dichroic elements, such as dichroic mirror, configured to split a measurement beam from one or more of the plurality of energy beams 144.
The plurality of energy beams 144 emitted by the respective diode emitters 304 of the plurality of diode arrays 302 may respectively become incident upon the build plane 130 in the form of a beam spot 322. A plurality of beam spots 322 corresponding to respective ones of the plurality of energy beams 144 may become incident upon the build plane 130 in the form of a pattern, such as a linear or curvilinear pattern of beam spots 322. Respective beam spots 322 may be adjacent to one another and/or partially overlapping with one another.
The one or more lenses of the beam conditioning assembly 306 may be configured and arranged to provide an array of energy beams 144 that are spaced apart from one another by a beam pitch (PB). The one or more lenses of the beam conditioning assembly 306 may be configured and arranged to provide an array of energy beams 144 with a beam pitch (PB) between adjacent energy beams 144 suitable for providing an alternating pattern or sequence of beam spots 322. The alternating pattern or sequence of beam spots 322 may be provided by a plurality of laser diode arrays 302. The plurality of laser diode arrays 302 may be configured and arranged with a suitable space between adjacent energy beams 144 to provide the alternating pattern or sequence of beam spots 322. The alternating pattern or sequence of beam spots 322 may provide a beam pitch (PB) that is less than or equal to the diode pitch ( of the respective laser diode arrays 302. For example, one or more optical elements of the beam conditioning assembly 306 and/or the beam focusing assembly 316 (
The space between adjacent energy beams 144 and/or adjacent beam spots 322 may be determined based at least in part on the diode pitch (PD) of the diode emitters 304 and the width (wD) of the diode emitters 304. As shown in
A cross-sectional dimension of respective ones of the plurality of beam spots 322 and/or energy beams 144 may be determined based at least in part on the Lagrange invariant. The one or more lenses of the beam conditioning assembly 306 may be configured to collimate and/or otherwise condition the respective energy beams such that the beam spots may become incident upon the powder bed 138 with suitable spacing to allow for the alternating pattern or sequence of beam spots 322. The respective beam spots 322 in the alternating pattern may be provided by respective ones of a plurality of laser diode arrays 302 and/or by respective ones of a plurality of irradiation devices 142.
In some embodiments, an alternating pattern of beam spots 322 may be suitable for additively manufacturing three-dimensional objects with high quality requirement when the respective energy beams 144 exhibit good beam quality. The quality of an energy beam 144 may be influenced by any one or more of a plurality of quality parameters, such as beam profile, waist position, intensity, caustic, spot size, and/or focal length, as well as combinations of these. The quality of an energy beam 144 may be described with reference to a beam quality factor (M2) according to ISO Standard 11146. The beam quality factor (M2) represents a variation of a beam from a diffraction-limited Gaussian beam with the same wavelength. The beam quality factor (M2) may be described according to the following relationship:
where (θ) is the half-angle beam divergence, (W0) is the beam radius at the beam waist, (λ) is the wavelength. A diffraction-limited Gaussian beam has an M2 value of 1.0. In some embodiments, the presently disclosed energy beam systems 134, irradiation devices 142, and/or methods may utilize an energy beam 144 with an M2 value of from about 1.05 to about 2.0, such as from about 1.05 to about 1.5, such as from about 1.05 to about 1.2, or such as from about 1.05 to about 1.15.
As shown in
Referring now to
The second plurality of beam spots 322 may be longitudinally offset from the first plurality of beam spots 322 with respect to a distance and/or a time delay suitable to reduce the tendency for adjacent build points 504 to introduce thermal variability, thereby allowing for a more uniform power density and/or improved controllability of the power density at the respective build points 504. For example, a first row of beam spots 322 may propagate across the powder bed 138 with a suitable lateral space between them, followed by a second row of beam spots 322 with a suitable space lateral between them and laterally offset from the first row of beam spots 322. The first row of beam spots 322 may scan a corresponding plurality of first hatch lines across the powder bed 138. The second row of beam spots 322 may scan a corresponding second plurality of hatch lines across the powder bed 138. The lateral offset between the first and second row of beam spots 322 may be configured and arranged such that the second plurality of hatch lines fill in the spaces between adjacent one of the first plurality of hatch lines resulting from the first plurality of beam spots 322 being scanned across the powder bed 138 ahead of the second plurality of beam spots 322.
As shown, for example, in
The diode offset distance (OD) between respective laser diode arrays 302 may provide a beam offset distance (OB) with respect to energy beams 144 emitted by the respective diode emitters 304. The beam offset distance (OB) may be determined with reference to a transverse axis (AT). The beam offset distance (OB) may include a lateral beam offset. For example, the irradiation device 142 may include a first laser diode array 302 and a second laser diode array 302 oriented relative to an optical axis (A) with a diode offset distance (OD) relative to one another. The diode offset distance (OD) between the first and second laser diode array 302 may be determined relative to the optical axis (A) and/or relative to respective diode emitters 304. The diode offset distance (OD) between the first and second laser diode array 302 may be configured to provide a corresponding beam offset distance (OB) between respective energy beams 144 emitted by a first diode emitter 304 of the first laser diode array 302 and a second diode emitter 304 emitted by the second laser diode array 302. For example, a first laser diode array 302 may emit a first plurality of energy beams 144 and a second laser diode array may emit a second plurality of energy beams 144, and respective ones of the first plurality of energy beams 144 may be laterally offset from respective ones of the second plurality of energy beams 144 by a beam offset distance (OB) determined with reference to a transverse axis (AT) of the build array. A beam offset distance (OB) between a first energy beam 144 corresponding to the first laser diode array 302 and a second energy beam 144 corresponding to a second laser diode array 302 may be oriented perpendicular to an irradiation direction 400 of the irradiation device 142 relative to the build plane 130.
A diode offset distance (OD) between a first laser diode array 302 and a second layer diode array 302 may be based at least in part on a diode pitch (PD) of the first laser diode array 302 and/or the second layer diode array 302. In some embodiments, the diode offset distance (OD) between the first laser diode array 302 and the second layer diode array 302 may be less than the diode pitch (PD) of the first laser diode array 302 and/or the second layer diode array 302. For example, as shown in
In some embodiments, the diode offset distance (OD) between the first laser diode array 302 and the second layer diode array 302 may be based at least in part on a diode width (wD) of the diode emitters 304 the first laser diode array 302 and/or the second layer diode array 302. For example, the diode offset distance (OD) between the first laser diode array 302 and the second layer diode array 302 may be equal to or greater than, such as a multiple of, the diode width (wD) of the diode emitters 304. As shown in
Still referring to
For example, as shown in
Additionally, or in the alternative, as shown in
The respective energy beams 144 from the offset laser diode arrays 302 may become incident upon a build plane 130 defined by a powder bed 138. The locations on the build plane 130 irradiated by the energy beams 144 may be described with reference to a build array 502 that includes a plurality of build points 504. The respective build points 504 in the build array 502 may be identified with reference to a coordinate system, such as an (X,Y,Z) cartesian coordinate system.
As shown in
The beam spots 322 may propagate across the build array 502 with relative motion between the build plane 130 and the plurality of energy beams 144, such as by movement of the one or more irradiation devices 142 and/or by movement of the build plane 130. As shown in
As shown in
As shown in
The longitudinally alignment and/or offset between the plurality of beam spots 322 corresponding to the first plurality of energy beams 144 from the first laser diode array 302 and the plurality of beam spots 322 corresponding to the second plurality of energy beams 144 from the second laser diode array 302 may be described with reference to time in an irradiation sequence, such as with reference to one or more time intervals and/or one or more instants in time during the irradiation sequence. As shown in
The first time may include a time interval or an instant in time. Additionally, or in the alternative, the second time may include a time interval or an instant in time. As shown in
As shown in
As shown in
As shown in
The configurations and arrangements of the laser diode arrays 302 described with reference to
In some embodiments, the build points 504 of the build array 502 may have a pixel width (wP) that correspond to the width of the beam spots 322 from the energy beams 144 emitted by the diode emitters 304 of the diode arrays 302. For example, the pixel width (wP) and the width of the beam spots 322 may respectively be from about 1 micrometer (μm) to about 500 μm, such as from about 25 μm to about 250 μm, such as from about 10 μm to about 100 μm, such as from about 25 μm to about 50 μm, such as from about 50 μm to about 100 μm, or such as from about 100 μm to about 150 μm. In some embodiments, the pixel width (wP) and the beam spots 322 may differ from one another by about 1 μm to about 250 μm, such as from about 10 μm to about 100 μm , such as from about 1μm to about 50 μm, such as from about 10 μm to about 25 μm, such as by less than about 100 μm, such as by less than about 50 μm, such as by less than about 25 μm, such as by less than about 10 μm, or such as by less than about 5 μm.
In some embodiments, the pixel width (wP) and/or the beam spots 322 may be about 50% of the diode pitch (PD), such as from about 30% to about 70% of the diode pitch (PD), or such as from about 40% to about 60% of the diode pitch (PD).
In some embodiments, the beam offset distance (OB) between adjacent energy beams 144 of the first and second laser diode arrays 302 may be a multiple of from about 1× of the diode width (wD) to about 5× of the diode width (wD), such as from about 1× of the diode width (wD) to about 2× of the diode width (wD), or such as from about 2× of the diode width (wD) to about 5× of the diode width (wD).
In some embodiments, the laser diode arrays 302 may provide an energy density per beam spot 322 of from about 0.1 W/cm2 to about 500 W/cm2, such as from about 1 W/cm2 to about 100 W/cm2, such as from about 50 W/cm2 to about 250 W/cm2, such as from about 250 W/cm2 to about 500 W/cm2. In some embodiments, the diode emitters 304 may be configured to pulse at a desired pulse frequency. The pulse frequency may be constant or variable. In some embodiments, the pulse frequency may be from about 10 MHz to about 100 GHz, such as from about 10 MHz to about 100 MHz, such as from about 100 MHz to about 250 MHz, such as from about 250 MHz to about 500 MHz, such as from about 500 MHz to about 1 GHz, such as from about 1 GHz to about 50 GHz, or such as from about 50 GHz to about 100 GHz. In some embodiments, the pulse frequency may be varied to provide a desired energy density to the powder bed 138.
The beam spots may have any desired cross-sectional profile, such as round, oval, square, rectangular, or any other suitable cross-sectional profile. The energy beams 144 may exhibit any desired intensity profile, such as a Gaussian profile, a top-hat profile, or any other suitable intensity profile.
The energy beams 144 may have a wavelength in the ultraviolet spectrum (about 1 nanometer (nm) to about 400 nm), the visible spectrum (about 400 nm to about 750 nm), and/or the near-infrared spectrum (about 750 nm to about 2,500 nm). For example, the energy beams 144 may have a wavelength of from about 300 nm to about 2000 nm, such as from 400 nm to about 1,100 nm, or such as from about 1,000 nm to about 1,100 nm.
Referring now to
As shown in
In some embodiments, the number of rows of diode emitters 304 may be proportional to a ratio of the diode width (wD) to the diode pitch (PD). The respective rows of diode emitters 304 may be laterally offset by a diode offset distance (OD) that corresponds or equates to the diode width (wD). The diode offset distance (OD) may be equal to the diode width (wD), or the diode offset distance (OD) may be less than the diode width (wD) or greater than, such as a multiple of, of the diode width (wD). For example, the number of rows of diode emitters 304 may be described with reference to the following relationship: N=(PD/wD)/kD, where kD is a diode overlap factor and N is the number of rows of diode emitters 304. The diode overlap factor (kD) describes a lateral overlap with respect to diode emitters 304 that provide laterally adjacent beam spots 322. A diode overlap factor of 1.0 represents diode emitters 304 that are laterally offset by a diode width (wD). As shown in
The diode offset distance (OD) may provide a corresponding beam offset distance (OB). The beam offset distance (OB) may correspond or equate to the diode offset distance (OD). The beam offset distance (OB) may be equal to the diode offset distance (OD), or the beam offset distance (OB) may be a less than the diode offset distance (OD) or a multiple of the diode offset distance (OD). For example, the beam offset distance (OB) may be described with reference to the following relationship: OB=OD√kB, where kB is a focus factor of the respective energy beams. The focus factor represents the extent to which the lateral position of respectively adjacent beam spots 322 are augmented by a beam focusing assembly 316 and/or one or more focusing lenses 320 thereof augmenting a lateral position of corresponding energy beams 144, for example, causing the respective beam spots 322 to become closer together or further apart. The focus factor may be from about 0.1 to about 1.0, such as from about 0.3 to about 0.7, or such as from about 0.7 to about 1.0.
The diode offset distance (OD) and/or the beam offset distance (OB) may be configured to orient a plurality of energy beams 144 corresponding to the respective diode emitters 304 to provide beam spots 322 that become incident upon build points 504 of a build array 502. The beam offset distance (OB) may provide a corresponding pixel width (wP) determined between beam spots 322 and/or build points 504 of the build array 502. The pixel width (wP) may correspond or equate to the beam offset distance (OB). Additionally, or in the alternative, the pixel width (wP) may correspond or equate to the diode width (wD). The pixel width (wP) may be equal to the beam offset distance (OB) and/or the diode width (wD), or the pixel width (wP) may be a less than the beam offset distance (OB) and/or diode width (wD), or the pixel width (wP) may be a multiple of the beam offset distance (OB) and/or diode width (wD).
In some embodiments, the pixel width (wP) may be less than the diode pitch diode pitch (PD). Additionally, or in the alternative, the pixel width (wP) may be proportional to a ratio of the diode pitch (PD) to the number of rows of diode emitters 304. For example, the pixel width (wP) may be described with reference to the following relationship: wP=(PD/N)/kP, where kP is a pixel overlap factor (kP), and N is the number of rows of diode emitters 304. The pixel overlap factor may be from about 0.1 to about 2.0, such as from about 0.1 to about 0.5, such as from about 0.5 to about 1.0, such as from about 1.0 to about 1.5, or such as from about 1.5 to about 2.0. As shown in
As shown in
The lateral offset may be configured such that spaces between adjacent one of the first plurality of hatch lines are filled in by hatch lines formed by a row of beam spots 322 from a row of diode emitters 304 preceded by at least one intermediate row of diode emitters 304. Respective rows of diode emitter 304 that provide abutting and/or partially overlapping hatch lines may be separated by at least one row of diode emitters 304. For example, a first and third row of diode emitters 304 may provide beam spots 322 that form abutting and/or partially overlapping hatch lines, and the first and third row of diode emitters 304 may be separated by at least a second row of diode emitters 304. In some embodiments, the beam offset distance (OB) may provide suitable spacing to allow for some cooling and/or melt pool contraction prior to a sequential beam spots 322 abutting and/or partially overlapping a hatch line, whether in a solidified or partially molten condition.
By way of illustration, as shown in
A third or subsequent row of diode emitters 304 may emit a third or subsequent plurality of energy beams 144 that provide a third or subsequent plurality of beam spots 322. The third or subsequent plurality of beam spots 322 may be spaced apart by the beam pitch (PB). A third or subsequent plurality of hatch lines formed by the third or subsequent plurality of beam spots 322 may be spaced apart by a beam pitch (PB). The third or subsequent plurality of beam spots 322 may occupy a space between respective ones of a first hatch line formed by a first beam spot 322 and a second hatch line formed by a second beam spot 322. A third beam spot 322 propagating across the build array 502 subsequent to a second beam spot 322 may be abutting and/or partially overlapping a first hatch line formed by a first beam spot 322. A fourth beam spot 322 propagating across the build array subsequent to a third beam spot may be abutting and/or partially overlapping a second hatch line formed by a second beam spot 322. A width of the build array 502 corresponding to the beam pitch (PB) may be sequentially irradiated by respective beam spots 322 corresponding to sequential rows of laser diode arrays, with each sequential beam spot 322 being laterally offset by at least a multiple of 2× the diode width (wD).
In some embodiments, as shown in
As shown in
Referring now to
As shown in
In some embodiments, an exemplary laser diode array 302 may have a width of from about 10 millimeters (mm) to about 100 mm, such as from about 10 mm to about 50 mm, such as from about 10 mm to about 25 mm, or such as from about 25 mm to about 75 mm. An exemplary irradiation device 142 may include any suitable number of laser diode arrays respectively configured and arranged laterally adjacent to one another. For example, an irradiation device 142 may include from 2 to 10 laterally adjacent laser diode arrays 302, such as from 2 to 5, or such as from 5 to 10 laterally adjacent laser diode arrays 302. The number of laterally adjacent laser diode arrays 302 may be determined based at least in part on a desired scan field width. The laterally adjacent laser diode arrays 302 may provide a scan field that has a width of from about 50 mm to about 1,000 mm, such as from about 50 mm to about 100 mm, such as from about 100 mm to about 250 mm, such as from about 250 mm to about 500 mm, or such as from about 500 mm to about 1,000 mm.
As shown in
As shown in
In some embodiments, as shown, for example, in
In some embodiments, as shown, for example, in
Referring now to
As shown in
As shown in
Respective build points 504 may receive irradiation from a plurality of energy beams 144 respectively corresponding to a plurality of diode emitters 304. The plurality of energy beams 144 may propagate incrementally across the build array such that the plurality of build points receive irradiation from at least some of the plurality of energy beams 144 with relative motion between the plurality of energy beams 144 and the build plane 130, and/or with relative motion between the irradiation device 142 and the build plane 130. Additionally, or in the alternative, the mapping of the plurality of diode emitters 304 to the build points 504 may increment with relative motion between the plurality of energy beams 144 and the build plane 130, and/or with relative motion between the irradiation device 142 and the build plane 130. The plurality of build points 504 may receive irradiation from at least some of the plurality of energy beams 144 corresponding to respective ones of the plurality of diode emitters 304 in a respective column. For example, a build point 504 in column (Y2B) of the build array 502 may receive irradiation from a plurality of energy beams corresponding to a plurality of diode emitters 304 in column (Y2D) of the one or more laser diode arrays 302. Additionally, or in the alternative, respective ones of the plurality of diode emitters 304 in a respective column (e.g., column Y2D) may respectively provide a fraction of the total energy imparted to a respective build point 504 (e.g., a build point 504 in column Y2B). For example, respective ones of the plurality of diode emitters 304 in a respective column of the one or more laser diode arrays 302 may respectively provide a pro-rata portion of the total energy imparted to a respective build point 504. Additionally, or in the alternative, respective ones of the plurality of diode emitters 304 in a respective column of the one or more laser diode arrays 302 may respectively provide a weighted portion of the total energy imparted to a respective build point 504. The weighted portion may differ as between respective ones of the plurality of diode emitters 304 in the respective column of the one or more laser diode arrays 302.
As depicted in
At a point in the irradiation sequence depicted in
As shown in
The irradiation sequence may similarly increment as shown, for example, in
As shown in
As depicted in
Now turning to
As shown in
The controller 900 may be communicatively coupled with an additive manufacturing machine 102. The controller 900 may be communicatively coupled with one or more components of an additive manufacturing machine 102, such as one or more components of an energy beam system 134 and/or an irradiation device 142, such as a beam generation device 300, a laser diode array 302, and/or a positioning system 150, and/or any one or more other elements thereof. The controller 900 may also be communicatively coupled with a management system 106 and/or a user interface 108.
The controller 900 may include one or more computing devices 904, which may be located locally or remotely relative to an additive manufacturing machine 102, an energy beam system 134, and/or an irradiation device 142. The one or more computing devices 904 may include one or more processors 906 and one or more memory devices 908. The one or more processors 906 may include any suitable processing device, such as a microprocessor, microcontroller, integrated circuit, logic device, and/or other suitable processing device. The one or more memory devices 908 may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard drives, flash drives, and/or other memory devices 908.
As used herein, the terms “processor” and “computer” and related terms, such as “processing device” and “computing device”, are not limited to just those integrated circuits referred to in the art as a computer, but broadly refers to a microcontroller, a microcomputer, a programmable logic controller (PLC), an application specific integrated circuit, and other programmable circuits, and these terms are used interchangeably herein. A memory device 908 may include, but is not limited to, a non-transitory computer-readable medium, such as a random access memory (RAM), and computer-readable nonvolatile media, such as hard drives, flash memory, and other memory devices. Alternatively, a floppy disk, a compact disc-read only memory (CD-ROM), a magneto-optical disk (MOD), and/or a digital versatile disc (DVD) may also be used.
As used herein, the term “non-transitory computer-readable medium” is intended to be representative of any tangible computer-based device implemented in any method or technology for short-term and long-term storage of information, such as, computer-readable instructions, data structures, program modules and sub-modules, or other data in any device. The methods described herein may be encoded as executable instructions embodied in a tangible, non-transitory, computer readable media, including, without limitation, a storage device and/or a memory device. Such instructions, when executed by a processor, cause the processor to perform at least a portion of the methods described herein. Moreover, as used herein, the term “non-transitory computer-readable medium” includes all tangible, computer-readable media, including, without limitation, non-transitory computer storage devices, including, without limitation, volatile and nonvolatile media, and removable and non-removable media such as a firmware, physical and virtual storage, CD-ROMs, DVDs, and any other digital source such as a network or the Internet, as well as yet to be developed digital means, with the sole exception being a transitory, propagating signal.
The one or more memory devices 908 may store information accessible by the one or more processors 906, including computer-executable instructions 910 that can be executed by the one or more processors 906. The instructions 910 may include any set of instructions which when executed by the one or more processors 906 cause the one or more processors 906 to perform operations, including irradiation operations, calibration operations, and/or additive manufacturing operations. Additionally, or in the alternative, the instructions, when executed by the one or more processors 906, may cause the one or more processors 906 to perform an irradiation sequence as described herein.
The memory devices 908 may store data 912 accessible by the one or more processors 906. The data 912 can include current or real-time data 912, past data 912, or a combination thereof. The data 912 may be stored in a data library 914. As examples, the data 912 may include data 912 associated with or generated by an additive manufacturing system 100 and/or an additive manufacturing machine 102, including data 912 associated with or generated by the controller 900, an additive manufacturing machine 102, an energy beam system 134, one or more irradiation devices 142, one or more beam generation devices 300, one or more laser diode arrays 302, one or more positioning systems 150, a management system 106, a user interface 108, and/or a computing device 904, such as operational data 912 and/or calibration data 912 pertaining thereto. The data 912 may also include other data sets, parameters, outputs, information, associated with an additive manufacturing system 100 and/or an additive manufacturing machine 102.
The one or more computing devices 904 may also include a communication interface 916, which may be used for communications with a communication network 918 via wired or wireless communication lines 920. The communication interface 916 may include any suitable components for interfacing with one or more network(s), including for example, transmitters, receivers, ports, controllers, antennas, and/or other suitable components. The communication interface 916 may allow the computing device 904 to communicate with various nodes on the communication network 918, such as nodes associated with the additive manufacturing machine 102, the energy beam system 134, the one or more irradiation devices 142, the one or more beam generation devices 300, one or more laser diode arrays 302, one or more positioning systems 150, the management system 106, and/or the user interface 108. The communication network 918 may include, for example, a local area network (LAN), a wide area network (WAN), SATCOM network, VHF network, a HF network, a Wi-Fi network, a WiMAX network, a gatelink network, and/or any other suitable communication network 918 for transmitting messages to and/or from the controller 900 across the communication lines 920. The communication lines 920 of communication network 918 may include a data bus or a combination of wired and/or wireless communication links.
The communication interface 916 may allow the computing device 904 to communicate with various components of an additive manufacturing system 100 and/or an additive manufacturing machine 102 communicatively coupled with the communication interface 916 and/or communicatively coupled with one another. The communication interface 916 may additionally or alternatively allow the computing device 904 to communicate with the management system 106 and/or the user interface 108. The management system 106 may include a server 922 and/or a data warehouse 924. As an example, at least a portion of the data 912 may be stored in the data warehouse 924, and the server 922 may be configured to transmit data 912 from the data warehouse 924 to the computing device 904, and/or to receive data 912 from the computing device 904 and to store the received data 912 in the data warehouse 924 for further purposes. The server 922 and/or the data warehouse 924 may be implemented as part of a control system 104 and/or as part of the management system 106.
Now turning to
As shown in
In some embodiments, the exemplary method 1000 may include irradiating the powder bed 138 with a first plurality of energy beams 144 corresponding to a first row of diode emitters 304 and irradiating the powder bed 138 with a second plurality of energy beams 144 corresponding to a second row of diode emitters 304. The first plurality of energy beams 144 may provide a corresponding first plurality of beam spots 322 incident upon a build array 502 defined by the powder bed 138 and the second plurality of energy beams 144 may provide a corresponding second plurality of beam spots 322 incident upon the powder bed 138. The first plurality of beam spots 322 and the second plurality of beam spots 322 may be arranged in a pattern or sequence such that beams spots 322 that become incident upon laterally adjacent build points 504 of the build array 502 are longitudinally offset from one another.
Additionally, or in the alternative, in some embodiments, an exemplary method 1000 may include irradiating the powder bed 138 with a plurality of rows of diode emitters 304, for example, as described with reference to
Further aspects of the presently disclosed subject matter are provided by the following clauses:
1. An irradiation device for additively manufacturing three-dimensional objects, the irradiation device comprising: a beam generation device comprising a plurality of laser diode arrays, wherein respective ones of the plurality of laser diode arrays comprise a plurality of diode emitters respectively configured to emit an energy beam; wherein the plurality of laser diode arrays are longitudinally offset relative to one another; and wherein the plurality of laser diode arrays are laterally offset relative to one another.
2. The irradiation device of any clause herein, wherein the plurality of laser diode arrays are longitudinally offset relative to one another by an array offset distance determined relative to an optical axis of the respective ones of the plurality of laser diode arrays.
3. The irradiation device of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the array offset distance is uniform as between respective ones of the plurality of laser diode arrays.
4. The irradiation device of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the array offset distance differs as between respective ones of the plurality of laser diode arrays.
5. The irradiation device of any clause herein, wherein the plurality of laser diode arrays are laterally offset relative to one another by a diode offset distance, the diode offset distance determined relative to an optical axis of the respective ones of the plurality of laser diode arrays
6. The irradiation device of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the diode offset distance is uniform as between respective ones of the plurality of laser diode arrays.
7. The irradiation device of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the diode offset distance differs as between respective ones of the plurality of laser diode arrays.
8. The irradiation device of any clause herein, wherein the plurality of laser diode arrays respectively emit a plurality of energy beams, respective ones of the plurality of energy beams emitted from corresponding ones of the plurality of diode emitters; wherein the plurality of energy beams provide a corresponding plurality of beam spots incident upon a build array defined by a powder bed disposed below the irradiation device, the plurality of beam spots arranged in a pattern or sequence such that beams spots that become incident upon laterally adjacent build points of the build array are longitudinally offset from one another.
9. The irradiation device of any clause herein, wherein at least some beams spots are longitudinally offset from one another in an alternating pattern or sequence.
10. The irradiation device of any clause herein, wherein plurality of energy beams provide a linear scan field comprising a first plurality of beam spots laterally spaced apart from one another followed by a second plurality of beam spots laterally spaced apart from one another; wherein the first plurality of beam spots and the second plurality of beam spots are longitudinally offset from one another with reference to a longitudinal axis of the build array, and wherein the first plurality of beam spots and the second plurality of beam spots are laterally offset from one another with reference to a transverse axis of the build array.
11. The irradiation device of any clause herein, wherein a first one of the plurality of laser diode arrays is configured to emit a first plurality of energy beams, and a second one of the plurality of laser diode arrays is configured to emit a second plurality of energy beams, wherein respective ones of the first plurality of energy beams are laterally offset from respective ones of the second plurality of energy beams by a beam offset distance determined with reference to a transverse axis of the build array.
12. The irradiation device of any clause herein, wherein the first plurality of energy beams provide a first plurality of beam spots that become incident upon and propagate across the build array as a first row and wherein the second plurality of energy beams provide a second plurality of beam spots that become incident upon and propagate across the build array as a second row.
13. The irradiation device of any clause herein, wherein the first row and the second row are longitudinally offset from one another by a distance of at least one pixel width of the build array, the pixel width defined between build points of the build array.
14. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein the diode offset distance is less than the diode pitch.
15. The irradiation device of any clause herein, wherein the diode offset distance is from 10% of the diode pitch to 90% of the diode pitch.
16. The irradiation device of any clause herein, wherein the plurality of diode emitters have a diode width, and wherein the diode offset distance is equal to or greater than the diode width.
17. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein adjacent beam spots have a beam pitch that is less than the diode pitch.
18. The irradiation device of any clause herein, wherein the plurality of beam spots incident upon the build array have a spacing corresponding to a pixel width defined between build points of the build array, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein the pixel width is smaller than the diode pitch.
19. The irradiation device of any clause herein, wherein the pixel width of the build array is from 1 micrometer to 500 micrometers.
20. The irradiation device of any clause herein, wherein the irradiation device is configured to provide beam spots that have a width of from 1 micrometer to 500 micrometers.
21. The irradiation device of any clause herein, wherein the plurality of laser diode arrays are configured to provide an energy density per beam spot of from 0.1 W/cm2 to 500 W/cm2.
22. The irradiation device of any clause herein, wherein the plurality of laser diode arrays have a pulse frequency of from 10 MHz to 100 GHz.
23. The irradiation device of any clause herein, wherein the plurality of laser diode arrays are configured to emit energy beams that have a wavelength in the ultraviolet spectrum, the visible spectrum, the near-infrared spectrum, or the infrared spectrum.
24. The irradiation device of any clause herein, the plurality of laser diode arrays respectively comprise a plurality of rows of diode emitters.
25. The irradiation device of any clause herein, wherein a cross-sectional dimension of respective ones of the plurality of beam spots is determined based at least in part on a Lagrange invariant.
26. The irradiation device of any clause herein, wherein the Lagrange invariant is from about 2.5 micrometers to about 90 micrometers.
27. The irradiation device of any clause herein, comprising: a beam conditioning assembly be disposed downstream from the beam generation device, the beam conditioning assembly comprising one or more collimating lenses, wherein the one or more collimating lenses are configured to collimate respective ones of a plurality of energy beams emitted by corresponding ones of the plurality of diode emitters such that the plurality of beam spots corresponding to the plurality of energy beams become incident upon the build array arranged in the pattern or sequence.
28. The irradiation device of any clause herein, wherein 1 the plurality of diode emitters are spaced apart from one another by a diode pitch of from 25 micrometers to 250 micrometers.
29. The irradiation device of any clause herein, wherein the plurality of diode emitters have a diode width of from 50 micrometers to 300 micrometers.
30. The irradiation device of any clause herein, wherein the irradiation device is configured to provide a plurality of energy beams with an M2 value of from 1.05 to 2.0.
31. The irradiation device of any clause herein, comprising: a beam conditioning assembly be disposed downstream from the beam generation device, the beam conditioning assembly comprising one or more lenses, the one or more lenses comprising a fast-axis collimating lens and/or a slow-axis collimating lens.
32. The irradiation device of any clause herein, wherein the beam conditioning assembly comprises a beam homogenizer.
33. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein the one or more lenses of the beam conditioning assembly are configured and arranged to provide a plurality of energy beams that are spaced apart from one another by a beam pitch that is less than or equal to the diode pitch.
34. The irradiation device of any clause herein, wherein the beam pitch is from 10% to 95% of the diode pitch.
35. The irradiation device of any clause herein, comprising: a beam focusing assembly disposed downstream from the beam conditioning assembly, the beam focusing assembly comprising one or more focusing lenses.
36. The irradiation device of any clause herein, wherein the one or more focusing lenses comprises a fast-axis focusing lens and/or a slow-axis focusing lens.
37. The irradiation device of any clause herein, comprising: a positioning system, wherein the irradiation device is mounted to the positioning system, wherein the positioning system is configured to move the irradiation device.
38. The irradiation device of any clause herein, wherein the positioning system comprises a plurality of irradiation devices mounted thereto, respective ones of the plurality of irradiation devices configured according to claim 1.
39. The irradiation device of any clause herein, wherein the positioning system is configured to move the irradiation device at a rate of from 1 millimeters per second to 10 millimeters per second.
40. The irradiation device of any clause herein, wherein the plurality of diode emitters corresponding to respective ones of the plurality of laser diode arrays comprises one or more rows of diode emitters.
41. The irradiation device of any clause herein, wherein the plurality of diode emitters have a diode width and wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein the number of rows of diode emitters is proportional to a ratio of the diode width to the diode pitch.
42. The irradiation device of any clause herein, the plurality of laser diode arrays together define a plurality of rows of diode emitters, wherein respective ones of the plurality of rows of diode emitters are laterally offset relative to one another by the diode offset distance (OD).
43. The irradiation device of any clause herein, wherein the number of rows of diode emitters is defined by the following relationship: N=(PD/wD)//kD, where kD is a diode overlap factor and N is the number of rows of diode emitters, PD is the diode pitch, and wD is the diode width.
44. The irradiation device of any clause herein, wherein the beam offset distance is defined by the following relationship: OB=OD·kB, where OB is the beam offset distance, OD is the diode offset distance, kB is a focus factor of respective ones of the plurality of energy beams.
45. The irradiation device of any clause herein, wherein a pixel width of the build array is defined by the following relationship: wP=(PD/N)/kP, where wP is the pixel width, PD is the diode pitch, N is the number of rows of diode emitters, and kP is a pixel overlap factor (kP).
46. The irradiation device of any clause herein, wherein the plurality of diode emitters corresponding to respective ones of the plurality of laser diode arrays define a plurality of rows of diode emitters.
47. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein adjacent ones of the plurality of rows of diode emitters are laterally offset incrementally across a distance corresponding to the diode pitch.
48. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and the plurality of rows of diode emitters are laterally offset in an alternating or asynchronous pattern across a diode pitch (PD).
49. The irradiation device of any clause herein, wherein the plurality of diode emitters have a diode width, and wherein the alternating or asynchronous pattern comprises adjacent ones of the plurality of rows of diode emitters being laterally offset by at least twice the diode width.
50. The irradiation device of any clause herein, comprising: an irradiation carriage, wherein the plurality of laser diode arrays are coupled to the irradiation carriage; and one or more actuators, wherein a respective one of the one or more actuators is configured to adjust a position of at least one of the plurality of laser diode arrays coupled to the irradiation carriage.
51. The irradiation device of any clause herein, wherein the one or more actuators are respectively configured to provide a lateral positional adjustment and/or a longitudinal positional adjustment of the at least one of the plurality of laser diode arrays.
52. The irradiation device of any clause herein, comprising: an irradiation carriage, wherein the plurality of laser diode arrays are coupled to the irradiation carriage, wherein at least some of the plurality of laser diode arrays are arranged laterally adjacent to one another.
53. The irradiation device of any clause herein, wherein the plurality of diode emitters are spaced apart from one another by a diode pitch, and wherein respective laterally adjacent ones of the plurality of laser diode arrays are laterally spaced from one another by a distance that corresponds to a factor of the diode pitch.
54. The irradiation device of any clause herein, wherein respective ones of the plurality of laser diode arrays may have a width of from 10 millimeters to about 100 millimeters.
55. The irradiation device of any clause herein, wherein the plurality of laser diode arrays arranged laterally adjacent to one another comprising from 2 to 10 laser diode arrays arranged laterally adjacent to one another.
56. The irradiation device of any clause herein, wherein the plurality of laser diode arrays arranged laterally adjacent to one another has a scan field of from about 50 millimeters to about 1,000 millimeters.
57. The irradiation device of any clause herein, comprising: a plurality of diode array groups, the plurality of diode array groups respectively comprising at least some of the plurality of laser diode arrays; wherein the plurality of diode array groups are arranged longitudinally adjacent to one another and separated from one another by a group separation distance; wherein respective ones of the plurality diode arrays corresponding to the respective ones of the plurality of laser diode arrays belonging to a respective one of the plurality of diode array groups are longitudinally adjacent to one another and separated from one another by a row separation distance, wherein the group separation distance is larger than the row separation distance.
58. The irradiation device of any clause herein, wherein respective ones of the plurality of diode array groups are laterally offset by a group offset distance.
59. The irradiation device of any clause herein, comprising: a plurality of diode array sets, the plurality of diode array sets respectively comprising at least some of the plurality of diode array groups; wherein the plurality of diode array sets are arranged longitudinally adjacent to one another and separated from one another by a set separation distance; wherein the set separation distance is larger than the group separation distance.
60. The irradiation device of any clause herein, comprising: wherein the plurality of diode array sets comprises a first diode array set and a second diode array set, wherein a corresponding one of the plurality of laser diode arrays belonging to the first diode array set is configured to exhibit one or more irradiation parameters that differs from a corresponding one of the plurality of laser diode arrays belonging to the second diode array set, the one or more irradiation parameters comprising: beam power, beam intensity, intensity profile, wavelength, spot size, and/or spot shape.
61. The irradiation device of any clause herein, comprising: a plurality of diode array sets, the plurality of diode array sets respectively comprising at least some of the plurality of diode array groups; wherein the plurality of diode array sets comprises a first diode array set and a second diode array set, wherein a corresponding one of the plurality of laser diode arrays belonging to the first diode array set is configured to impart a quantity of heat to a powder bed that differs from a corresponding one of the plurality of laser diode arrays belonging to the second diode array set.
62. The irradiation device of any clause herein, wherein the first diode array set is configured to provide pre-heating, re-melting, and/or post-treating; and wherein the second diode array set is configured to provide lasing.
63. A method of additively manufacturing a three-dimensional object, the method comprising: irradiating a powder bed with a beam generation device comprising a plurality of laser diode arrays, wherein respective ones of the plurality of laser diode arrays comprise a plurality of diode emitters respectively configured to emit an energy beam; wherein the plurality of laser diode arrays are longitudinally offset relative to one another; and wherein the plurality of laser diode arrays are laterally offset relative to one another.
64. The method of any clause herein, wherein the plurality of laser diode arrays are longitudinally offset relative to one another by an array offset distance determined relative to an optical axis of the respective ones of the plurality of laser diode arrays.
65. The method of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the array offset distance is uniform as between respective ones of the plurality of laser diode arrays.
66. The method of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the array offset distance differs as between respective ones of the plurality of laser diode arrays.
67. The method of any clause herein, wherein the plurality of laser diode arrays are laterally offset relative to one another by a diode offset distance, the diode offset distance determined relative to an optical axis of the respective ones of the plurality of laser diode arrays.
68. The method of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the diode offset distance is uniform as between respective ones of the plurality of laser diode arrays.
69. The method of any clause herein, wherein the plurality of laser diode arrays includes at least three laser diode arrays, and wherein the diode offset distance differs as between respective ones of the plurality of laser diode arrays.
70. The method of any clause herein, comprising: applying a layer of powder material to the powder bed.
71. The method of any clause herein, comprising: irradiating the powder bed with a first plurality of energy beams corresponding to a first row of diode emitters and irradiating the powder bed with a second plurality of energy beams corresponding to a second row of diode emitters; wherein the first plurality of energy beams provide a corresponding first plurality of beam spots incident upon a build array defined by the powder bed and the second plurality of energy beams provide a corresponding second plurality of beam spots incident upon the powder bed; wherein the first plurality of beam spots and the second plurality of beam spots are arranged in a pattern or sequence such that beams spots that become incident upon laterally adjacent build points of the build array are longitudinally offset from one another.
72. The method of any clause herein, comprising: irradiating the powder bed with a plurality of rows of diode emitters, wherein respective build points of the build array receive irradiation sequentially from a plurality of energy beams, wherein respective ones of the plurality of energy beams that become incident upon a respective build point are respectively emitted by a diode emitter corresponding to longitudinally adjacent ones of the plurality of rows of diode emitters.
73. The method of any clause herein, wherein the method is performed using the irradiation device of any clause herein.
74. A computer-readable medium comprising computer-executable instructions, which when executed by a processor associated with an additive manufacturing machine, cause the additive manufacturing machine to perform a method comprising: irradiating a powder bed with a beam generation device comprising a plurality of laser diode arrays, wherein respective ones of the plurality of laser diode arrays comprise a plurality of diode emitters respectively configured to emit an energy beam; wherein the plurality of laser diode arrays are longitudinally offset relative to one another; and wherein the plurality of laser diode arrays are laterally offset relative to one another.
75. The computer-readable medium of any clause herein, wherein the computer-readable medium, when executed by a processor associated with an additive manufacturing machine, is configured to cause the additive manufacturing machine to perform the method of any clause herein.
This written description uses exemplary embodiments to describe the presently disclosed subject matter, including the best mode, and also to enable any person skilled in the art to practice such subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the presently disclosed subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The present application claims priority to U.S. Provisional Application Number 63/235,327 filed on Aug. 20, 2021, which is incorporated by reference herein for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 63235327 | Aug 2021 | US |
