Additive manufacturing systems including collocated recoaters and optics assemblies

Abstract

Additive manufacturing systems and related methods are disclosed. In some embodiments, a first motion stage may be used to move a recoater and an optics assembly. The optics assembly may be configured to direct laser energy from one or more laser energy sources towards a build plate. The recoater may be configured to form a layer of precursor material on the build plate. In some embodiments, a secondary housing formed of a composite material may be used.

Description

ADDITIVE MANUFACTURING SYSTEMS INCLUDING COLLOCATED RECOATERS AND OPTICS ASSEMBLIESRELATED APPLICATIONS

[0001] This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63 / 510,352, filed June 6, 2023, the content of which is incorporated by reference in its entirety for all purposes.FIELD

[0002] Disclosed embodiments are generally related to additive manufacturing systems including collocated recoaters and optics assemblies and related methods.BACKGROUND

[0003] Additive manufacturing systems employ various techniques to create three- dimensional objects from two-dimensional layers. After a layer of precursor material is deposited onto a build surface, a portion of the layer may be fused through exposure to one or more energy sources to create a desired two-dimensional geometry of solidified material within the layer. Next, the build surface may be indexed, and another layer of precursor material may be deposited. For example, in conventional systems, the build surface may be indexed downwardly by a distance corresponding to a thickness of a layer. This process may be repeated layer-by-layer to fuse many two-dimensional layers into a three-dimensional object.SUMMARY

[0004] In some embodiments, an additive manufacturing system comprises a first motion stage extending in a direction that is parallel to a first axis of a build plate of the additive manufacturing system and a recoater movably coupled to the first motion stage, wherein the recoater is configured to move along the first motion stage relative to the build plate and parallel to the first axis, and wherein the recoater is configured to form a layer of precursor material disposed on the build plate. The additive manufacturing system further comprises one or more laser energy sources and an optics assembly movably coupled to thefirst motion stage, wherein the optics assembly is configured to move along the first motion stage relative to the build plate and parallel to the first axis, and wherein the optics assembly is configured to direct laser energy from the one or more laser energy sources toward the build plate to melt at least a portion of the layer of precursor material disposed on the build plate.

[0005] In some embodiments, a method for additive manufacturing comprises moving an optics assembly parallel to a first axis of a build plate of an additive manufacturing system using a first motion stage and directing laser energy from one or more laser energy sources through the optics assembly and toward the build plate. The method further comprises melting at least a portion of a layer of precursor material disposed on the build plate, moving a recoater parallel to the first axis using the first motion stage, and forming a layer of the precursor material on the build plate.

[0006] In some embodiments, an additive manufacturing system comprises a primary housing, a secondary housing coupled to the primary housing, wherein the primary housing and the secondary housing define an interior volume, and a build plate disposed within the interior volume. The additive manufacturing system further comprises one or more laser energy sources, an optics assembly disposed within the interior volume, wherein the optics assembly is configured to direct laser energy from the one or more laser energy sources toward the build surface to melt at least a portion of a layer of material disposed on the build surface, and wherein the secondary housing is formed of a composite material, and wherein the secondary housing has an optical density of approximately OD-7 or greater.

[0007] In some embodiments, a method for additive manufacturing comprises directing laser energy from one or more laser energy sources through an optics assembly and toward a build plate of an additive manufacturing system and providing a primary housing and a secondary to form an interior housing, wherein the optics assembly and the build plate are in the interior housing. The method further comprises melting at least a portion of a layer of precursor material disposed on the build plate and wherein the secondary housing is formed of a composite material, and wherein the secondary housing has an optical density of approximately OD-7 or greater.

[0008] It should be appreciated that the foregoing concepts, and additional concepts discussed below, may be arranged in any suitable combination, as the present disclosure isnot limited in this respect. Further, other advantages and novel features of the present disclosure will become apparent from the following detailed description of various nonlimiting embodiments when considered in conjunction with the accompanying figures.

[0009] Other advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments of the disclosure when considered in conjunction with the accompanying figures.BRIEF DESCRIPTION OF DRAWINGS

[0010] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:

[0011] Fig. 1 shows a schematic representation of an additive manufacturing system according to some embodiments;

[0012] Fig. 2 shows an additive manufacturing system according to some embodiments;

[0013] Fig. 3 shows a laser energy source and emitted laser beam according to some embodiments;

[0014] Fig. 4 shows a side view of a recoater and build plate of an additive manufacturing system according to some embodiments;

[0015] Fig. 5A shows another side view of a recoater and build plate of an additive manufacturing system according to some embodiments;

[0016] Fig. 5B shows yet another side view of a recoater and build plate of an additive manufacturing system according to some embodiments;

[0017] Fig. 6A shows a further side view of a recoater and build plate of an additive manufacturing system with an unscraped layer of precursor material deposited on the build plate according to some embodiments;

[0018] Fig. 6B shows an even further side view of a recoater and build plate of an additive manufacturing system with a scraped layer of precursor material on the build plate according to some embodiments;

[0019] Fig. 7 shows an isometric view of a recoater and optics assembly of an additive manufacturing system according to some embodiments;

[0020] Fig. 8 shows a top view of a recoater and optics assembly of an additive manufacturing system according to some embodiments;

[0021] Fig. 9 shows a schematic representation of a flow diagram relating to a method for additive manufacturing of one or more parts according to some embodiments;

[0022] Fig. 10 shows an additive manufacturing system including a secondary housing according to some embodiments;

[0023] Fig. 11 shows a top view of an additive manufacturing system including a secondary housing according to some embodiments; and

[0024] Fig. 12 shows one embodiment of a recoater and optics assembly including a damper for use during potential impacts.DETAILED DESCRIPTION

[0025] Laser powder bed fusion (LPBF) is a layer-by-layer additive manufacturing technique. In LPBF, layers of precursor material are deposited by a recoater, and precursor material may be selectively fused using laser energy. The laser energy may be directed to the precursor material from one or more laser energy sources using movable mirrors (e.g., rotatable mirrors or galvanometer mirrors), moving an output coupled to the laser energy sources (e.g., using a gantry system), or a combination thereof. In systems where the laser energy sources are coupled to an optics assembly configured to directed laser energy beams emitted by the laser energy sources onto a build surface to form corresponding laser energy pixels thereon, the optics assembly may be moved relative to the build surface (e.g., using a gantry system). Regardless, it is desirable for the laser energy sources to be appropriately focused on the precursor material during fusion. To focus the laser energy sources on the layer of precursor material, the laser energy sources may be configured such that a focal plane associated with the laser energy sources may be aligned with the top most layer of precursor material forming the build surface disposed on the build plate of a system. If the lasers go in or out of focus (e.g., the focal plane is not aligned with the build surface), the effective spot size, shape, energy density, or other desired parameter of the laser energypixels may change from a desired parameter. This may result in a lack of fusion of the powder and / or other undesired part defects.

[0026] In additive manufacturing systems where an optics assembly coupled to a plurality of laser energy sources and a recoater are moved on separate gantries or other types of motion stages, the laser energy sources may go out of focus with respect to a build surface during movement (e.g., layer of precursor material) due to a lack of parallelism between a motion plane of the optics assembly and the build surface. The build surface may be established using a recoater blade of the recoater which may move along an axis that is parallel to a build surface formed on an exposed upper surface of a layer of precursor material disposed on a build plate of a system. In some embodiments, the recoater blade may include a straight edge that is oriented towards and contacts the layer of precursor material during a scraping procedure as the recoater blade is moved across the layer of precursor material to form the build surface. The inventors have recognized that aligning the plane of motion of the optics assembly with the plane of motion of the recoater system including the recoater blade such that the two motion planes may be parallel to one another may help to facilitate forming the build surface in a desired orientation relative to the optics assembly. For example, the recoater movement plane and the optics assembly movement plane may be aligned such that the recoater movement and the optics assembly movement planes are substantially parallel to one another.

[0027] The Inventors have recognized that aligning the motion plane of the recoater and the motion plane of the optics assembly to be substantially parallel may be challenging due to the recoater and the optics assembly having separate / different associated orientations and / or reference frames. For example, additive manufacturing systems having gantry-based movement systems may have different motion stages with separate associated reference frames for the recoater and the optics assembly. As such, the motion stages of the recoater and optics assembly may be misaligned with one another and accordingly the motion plane of the recoater and the motion plane of the optics assembly may also be misaligned with one another. For example, the motion stages of the recoater and the optics assembly may be configured such that the motion planes of the recoater and the optics assembly are not parallel with one another. The build surface that may be formed by the recoater (following the plane of motion of the recoater) accordingly may not be parallel with the motion plane of the opticsassembly, and thus, the location of the resulting build surface relative to a motion plane of the optics assembly may vary such that different portions of the build surface may be arranged at different lengths relative to a motion plane of the optics assembly. This change in relative location of the build surface may be associated with increased defect formation in parts being manufactured with such a system.

[0028] In view of the above, the Inventors have recognized that the recoater and the optics assembly of an additive manufacturing system may be configured to move on a single combined (e.g., the same) motion stage. Moving the recoater and the optics assembly on the same motion stage may eliminate the need to align separate reference frames associated with the movement of the recoater and the optics assembly on separate motion stages, thereby simplifying alignment and operation. Accordingly, time and cost associated with aligning the plane of motion of the recoater and the plane of motion of the optics assembly may be reduced while also providing improved accuracy for forming a build surface on a layer of precursor material disposed on a build plate. In some instances, the motion stage may be a linear motion stage and the recoater and the optics assembly may be configured to independently move linearly along the combined linear motion stage. In instances of a linear motion stage, the optics assembly and the recoater may move along the same linear axis of movement extending along a build surface of the additive manufacturing system, thereby making the directions of movement and motion planes of the recoater and the optics assembly inherently parallel with one another.

[0029] It should be understood that the motion stages used with the various embodiments disclosed herein may correspond to any appropriate motion stage capable of supporting and controlling the movement of a recoater, optics assembly, and / or other appropriate component. For example, in some embodiments the supports of a motion stage may include rails, rods, racks, grooves, threaded rods, any support surfaces, and any other appropriate type of supports. A motion stage coupled to a recoater, optics assembly, or other component may also include any appropriate movable components that may move along the corresponding one or more supports including but not limited to: bearings; recirculating ball or roller bearings, air bearings, crossed roller bearings, hydrostatic bearings, plain bearings, any other linear bearings, or any other appropriate bearings; wheels; gears; threaded drive nuts; and / or any other appropriate component capable of moving along a correspondingsupport of a motion stage. In some embodiments, the moveable components may be coupled to the recoater and / or the optics assembly and may be movably supported on or by the supports to allow movement of the recoater and / or optics assembly along a length of the supports. The supports and / or moveable components may optionally be automatically or manually lubricated as the disclosure is not limited in this fashion. For example, the supports and / or moveable components may be automatically or manually lubricated using any appropriate pumpable greases or lubricants.

[0030] In the various embodiments disclosed herein of an additive manufacturing system, a motion stage may be a linear motion stage and the recoater and the optics assembly may be configured to move linearly along a combined linear motion stage. In some embodiments, the motion stage may include opposing supports disposed on opposing sides of plane normal to a surface of a corresponding build plate. In some embodiments, such as the embodiments where the motion stage is a linear motion stage, the opposing supports may be parallel to one another.

[0031] A motion stage in the various embodiments described herein may also include one or more actuators configured to move the recoater, optics assembly, or other component along the motion stage in a direction of motion of the motion stage. The one or more actuators may be any appropriate actuator, including motors, linear motors, solenoids, pneumatic actuators, hydraulic actuators, any other appropriate mechanical actuator, electrical actuator, electromechanical actuator, hydraulic actuator, pneumatic actuator, any combination thereof, and any other appropriate actuator as the disclosure is not limited in this fashion. In some embodiments, where a motion stage includes two or more separate components, such as a recoater and an optics assembly, moveably coupled to the motion stage, the use of one or more linear motors configured to separately drive both components may be advantageous as detailed further below.

[0032] In embodiments where the recoater and the optics assembly move along the same motion stage, misalignment or variations in the movement of the recoater and the optics assembly along the same motion stage may still result in some slight misalignment between the motion planes such that the motion plane of the recoater and the motion plane of the recoater may not be perfectly parallel. As such, a normal direction of the motion plane of the recoater and a normal direction of the motion plane of the optics assembly may be orientedwithin about 50 microradians, 40 microradians, 30 microradians, 20 microradians, 10 microradians, and / or any other appropriate angle of each other. In some embodiments, the normal direction of the motion plane of the recoater and the normal direction of the motion plane of the optics assembly may preferable be oriented within 10 microradians of one another.

[0033] Additive manufacturing systems often fuse the precursor material within an inert atmosphere to avoid undesired interactions associated with the melted precursor material and any gas or other fluid present within the atmosphere. Maintaining the inert atmospheres involves maintaining a sealed volume that is isolated from the surrounding environment. As such, the additive manufacturing systems may include a housing configured to form a sealed volume having an inert atmosphere disposed within an internal volume formed therein in which the optics assembly, build plate, and recoater may be disposed.

[0034] While it may be desirable to maintain a sealed inert atmosphere within an additive manufacturing system, large additive manufacturing systems are complex, include many interacting parts, and are too large to simply contain within an integrally formed airtight housing disposed around the system. Accordingly, a housing for large additive manufacturing system typically includes a plurality of separate portions which may include appropriate access ports (e.g., movable panels and doors), pass throughs, and seals to enable access to appropriate portions of the additive manufacturing system while maintaining the sealed volume and associated atmosphere. Due to the potential to leak from these various features, the Inventors have recognized that it is desirable to reduce an overall internal volume of the additive manufacturing system. However, the gantry, optics, and other components included in the upper portion of an additive manufacturing system may be bulky and exhibit non-uniform geometries. Therefore, this typically results in upper portions of a system that are difficult to seal without including excess unfilled volume when using a simple housing geometry and / or through the use of multiple connected and sealed panels used to form more complex geometries. However, these arrangements made using typical bolted together panels with seals are leaky and / or may result in the presence of excessive amounts of unoccupied volume within the upper portion of the housing above the motion stages.

[0035] Following from the above, there is a desire to reduce the size and leakage rates associated with the sealed internal atmospheres of additive manufacturing systems. As such,the Inventors have recognized the benefits of a housing including a split construction between a lower primary housing and a upper secondary housing attached and sealed to the lower primary housing. The secondary housing may be integrally formed using a composite material which may help to reduce gas leakage from this portion of the housing due to a reduction in the number and size of seals associated with the upper portion of the additive manufacturing system. The secondary housing may be coupled to a primary housing to form (e.g., define) an interior volume, which may be sealed. Due to the secondary housing being made of a composite material, the secondary housing may be made with complex geometries that better conform to a shape and location of components disposed in an upper portion of the overall housing. In some embodiments, the composite material is a polymer ceramic composite material. This may help to reduce an overall volume of the atmosphere contained within the interior volume of the housing. The reduced volume and reduced gas leakage associated with such a construction may help reduce the time and volumes of gas needed to maintain the desired inert atmosphere which may result in increased overall print rates and decreased costs. Forming the secondary housing out of composite material may provide the additional benefit of reducing the weight of the secondary housing, while still providing sufficient structural support to the upper portion of the additive manufacturing system. Further, composite material may be easily formed in any appropriate size and / or geometry, including non-uniform geometries.

[0036] The Inventors have also recognized that not every composite material is appropriate for use with an additive manufacturing system due to the presence of high intensity laser energy that is emitted and reflected within the system during operation. Accordingly, to prevent the emission of high intensity laser radiation from within the system to a surrounding area, it may be desirable to use composite materials that are selected to reduce the amount of laser energy transmitted through the secondary housing to be below a desired threshold intensity. As discussed further below, blocking laser energy may involve blocking wavelengths of light associated with the laser energy used for fusing precursor material. This may be accomplished by forming the secondary housing out of a material that is substantially opaque to the laser energy (e.g., does not allow passage of the laser energy). As previously mentioned, the secondary housing may be formed of composite material, which may not be inherently opaque to the laser energy used in the LPBF additivemanufacturing system. Thus, a composite material used to form a secondary housing may include one or more additives, such as a filler material, as discussed further below to make the composite material opaque to the laser energy. As such, the inventors have recognized forming the secondary housing using composite material that may exhibit sufficient optical density (e.g., absorbance) in a wavelength range associated with the laser energy source may substantially prevent transmission of laser energy out from the additive manufacturing system may be advantageous.

[0037] In the various embodiments disclosed herein, an inert atmosphere may include an inert gas which may help to prevent oxidation of materials during a fusing process. For example, the atmosphere of the interior volume of an additive manufacturing system may be comprised substantially of one or more inert gasses (i.e., at least a majority of the atmosphere). For example, the inert gas may comprise a greater portion of the composition of atmosphere within the interior volume of the spray chamber as compared to a composition of the surrounding ambient (e.g., typical) atmosphere. The inert gas may include one or more selected from a group of nitrogen (e.g., N2), helium (e.g., He), neon (e.g., Ne), argon (e.g., Ar), krypton (e.g., Kr), xenon (e.g., Xe), and any other appropriate inert gas as the disclosure is not so limited.

[0038] In some embodiments, the atmosphere may include one or more inert gases in a volumetric percentage of less than or equal to approximately 100%, 99%, 95%, and / or any other appropriate percentage. The atmosphere may contain inert gas in a volumetric percentage of greater than or equal to 90%, 95%, 99%, and / or any other appropriate pressure. Combinations of the foregoing, including volume percentages between or equal to 90% and 100% are also contemplated, as well as other volumetric percentages. In some preferred embodiments, the atmosphere may comprise between or equal to 95% and 100%, 99% and 100%, or other desired range of compositions of the one or more inert gasses.

[0039] As noted above, the secondary housing of any of the embodiments disclosed herein may be formed with a composition and a thickness that is sufficient to be substantially opaque to laser energy, meaning the optical density of the secondary housing with respect to the wavelengths of light associated with the laser energy may be sufficient to reduce the emitted laser energy transmitted through the secondary housing to be less than a desired threshold intensity. For example, in some embodiments, the secondary housing may be madefrom a material and with a thickness such that it has an optical density of greater than or equal to about OD-7. For example, the optical density of the secondary housing may be between or equal to approximately OD-8 or OD-9. In other words, the secondary housing may be configured to reduce an intensity of transmitted light to be less than approximately 0.00001% (1 in 10,000,000) of the intensity of the laser energy that is incident on the interior surface of the secondary housing. Of course optical density ranges greater than those noted above are also possible.

[0040] As noted above, a composite material used with any of the embodiments disclosed herein may include a filler material to increase an optical density of the material. In addition to the strengthening fibers and / or particles and binder present in the composite material. It should be understood that any appropriate filler material may be used, including but not limited to carbon black, lamp black, iron oxide black, any other appropriate pigmentation material, any combination thereof, and any other appropriate filler that is substantially opaque to the laser energy emitted by an additive manufacturing system. In some embodiments, the binder may have a lower optical density relative to the filler material. Accordingly, the filler material may increase the optical density of the composite material according to some embodiments. Thus, increasing the amount of filler in the composite material may correspondingly increase the optical density of the material.

[0041] In some embodiments, a weight percentage of a filler of a composite material as disclosed herein may be less than or equal to approximately 20%, 18%, 16%, 14%, 12%, 10%, and / or any other appropriate weight percentage of a total weight of the composite. The weight percentage of the filler of the composite material may also be greater than or equal to 10%, 12%, 14%, 16%, 18%, 20%, and / or any other weight percentage of a total weight of the composite. Combinations of the foregoing, including weight percentages between or equal to 10% and 20% are also contemplated, though other percentages may also be used depending on the specific materials, as the present disclosure is not limited by the weight percentage of the filler of the composite material.

[0042] In addition to the filler, a composite material may include any appropriate reinforcing material (e.g., a reinforcing particle and / or fiber material). This may include, but is not limited to, fiberglass, carbon fiber, para-aramid fibers (e.g., Kevlar), and / or any combination thereof, and any other appropriate reinforcing fiber or particle useful forcomposite manufacturing. Any appropriate binder material may also be used, including but not limited to epoxy, polyurethane, any combination thereof, and any other appropriate binder for composite manufacturing.

[0043] In some embodiments, wavelengths of light associated with the laser energy from the optics assembly and the reflected laser energy as described herein may range from about 1050 nm to about 1100 nm, though other ranges of wavelengths of light associated a laser energy source may also be used. For example, in some embodiments, wavelengths of light from lasers used in laser powder bed fusion may typically range from about 1050 nm to about 1090 nm. However, it should be understood that the disclosure is in no way limited to the wavelengths of light associated with the laser energy. Regardless, the secondary housing may be substantially opaque to the range of wavelengths of light associated with the laser energy.

[0044] The secondary housing may be opaque at least to the wavelengths of light associated with the laser energy, and in some embodiments may be opaque to a broader range of wavelengths of light. For example, the secondary housing may also be opaque to any appropriate ranges of wavelengths of light associated with the additive manufacturing system, including any emitted electromagnetic radiation that may be between or equal to about 10 nm to about 1700 nm. This may include near infrared (NIR), short wave infrared (SWIR), plasma, visible light, and ultraviolet (UV), each of which may have an associated range of wavelengths. In some embodiments, Ultraviolet (UV) wavelengths of light may range from about lOnm to about 400 nm. In some embodiments, wavelengths of visible light may range from about 380 nm to about 700 nm. In some embodiments, wavelengths of NIR light may range from about 700 nm to about 1000 nm. In some embodiments, wavelengths of SWIR light may range from about 1000 nm to about 1700 nm. For example, the secondary housing may be opaque to wavelengths of light emitted from plasma which may correspond to wavelengths of light within the near-infrared (NIR) range, wavelengths associated with laser energy incident on a build surface which may be within the short-wave infrared (SWIR) range, and / or other appropriate ranges of wavelengths of light associated with a build process. As such, the filler material may be substantially opaque to any one or more of theaforementioned ranges of wavelengths of light corresponding to any appropriate optical density as described herein.

[0045] In some embodiments, incident laser spots on a build surface may be arranged in a line with a long dimension and a short dimension, or in an array. In either case, according to some aspects, a line, or array, of incident laser energy consists of multiple individual laser energy pixels arranged adjacent to each other that can have their respective power levels individually controlled. Each laser energy pixel may be turned on or turned off independently and the power of each pixel can be independently controlled. The resulting pixel-based line or array may then be scanned across a build surface to form a desired pattern thereon by controlling the individual pixels during translation of the optics assembly.

[0046] Depending on the particular embodiment, an additive manufacturing system according to the current disclosure may include any suitable number of laser energy sources. For example, in some embodiments, the number of laser energy sources may be at least 5, at least 10, at least 50, at least 100, at least 500, at least 1,000, at least 1,500, or more. In some embodiments, the number of laser energy sources may be less than 2,000, less than 1,500, less than 1,000, less than 500, less than 100, less than 50, or less than 10. Additionally, combinations of the above-noted ranges may be suitable. Ranges both greater and less than those noted above are also contemplated as the disclosure is not so limited.

[0047] Additionally, in some embodiments, a power output of a laser energy source (e.g., a laser energy source of a plurality of laser energy sources) may be between about 50 W and about 2,000 W (2 kW). For example, the power output for each laser energy source may be between about 100 W and about 1.5 kW, and / or between about 500 W and about 1 kW. Moreover, a total power output of the plurality of laser energy sources may be between about 500 W (0.5 kW) and about 4,000 kW. For example, the total power output may be between about 1 kW and about 2,000 kW, and / or between about 100 kW and about 1,000 kW.Ranges both greater and less than those noted above are also contemplated as the disclosure is not so limited.

[0048] Depending on the embodiment, an array of laser energy pixels (e.g., a line array or a two dimensional array) may have a uniform power density along one or more axes of the array including, for example, along the length dimension (i.e. the longer dimension) of a line array. In other instances, an array can have a non-uniform power density along eitherof the axes of the array by setting different power output levels for each pixel’s associated laser energy source. Moreover, individual pixels on the exterior portions of the array can be selectively turned off or on to produce an array with a shorter length and / or width. In some embodiments, the power levels of the various pixels in an array of laser energy may be independently controlled throughout an additive manufacturing process. For example, the various pixels may be selectively turned off, on, or operated at an intermediate power level to provide a desired power density within different portions of the array.

[0049] Generally, laser energy produced by a laser energy source has a power area density. In some embodiments, the power area density of the laser energy transmitted through an optical fiber is greater than or equal to 0.1 W / micrometer2, greater than or equal to 0.2 W / micrometer2, greater than or equal to 0.5 W / micrometer2, greater than or equal to 1 W / micrometer2, greater than or equal to 1.5 W / micrometer2, greater than or equal to 2 W / micrometer2, or greater. In some embodiments, the power area density of the laser energy transmitted through the optical fiber is less than or equal to 3 W / micrometer2, less than or equal to 2 W / micrometer2, less than or equal to 1.5 W / micrometer2, less than or equal to 1 W / micrometer2, less than or equal to 0.5 W / micrometer2, less than or equal to 0.2 W / micrometer2, or less. Combinations of these ranges are possible. For example, in some embodiments, the power area density of the laser energy transmitted through the optical fiber is greater than or equal to 0.1 W / micrometer2and less than or equal to 3 W / micrometer2.

[0050] Depending on the application, output of the optics assembly may be scanned across a build surface of an additive manufacturing system in any appropriate fashion. For example, in one embodiment, one or more galvo scanners may be associated with one or more laser energy sources to scan the resulting one or more laser pixels across the build surface. Alternatively, in other embodiments, an optics assembly may include an optics head that is associated with one or more appropriate actuators configured to translate the optics head in a direction parallel to a plane of the build surface to scan the one or more laser pixels across the build surface. In either case, it should be understood that the disclosed systems and methods are not limited to any particular construction for scanning the laser energy across a build surface of the additive manufacturing system.

[0051] For the sake of clarity, transmission of laser energy through an optical fiber is described generically throughout. However, with respect to various parameters such astransverse cross-sectional area, transverse dimension, transmission area, power area density, and / or any other appropriate parameters related to a portion of an optical fiber that the laser energy is transmitted through, it should be understood that these parameters refer to either a parameter related to a bare optical fiber and / or a portion of an optical fiber that the laser energy is actively transmitted through such as an optical fiber core, or a secondary optical laser energy transmitting cladding surrounding the core. In contrast, any surrounding cladding, coatings, or other materials that do not actively transmit the laser energy may not be included in the disclosed ranges.

[0052] Optical density as used herein describes the quantity of wavelengths of light which pass through a material. More specifically, optical density refers to the logarithm of the ratio of incident wavelengths of light to transmitted wavelengths of light. Optical density may sometimes be referred to as absorbance. Optical density is a dimensionless quantity; however, optical density units (OD) may be used to describe the magnitude of optical density associated with a material. For example, a material having an optical density of OD-1 would transmit approximately 10% of all incident wavelengths of light through the material, a material having an optical density of OD-2 would transmit approximately 1% of all incident wavelengths of light through the material, and a material having an optical density of OD-3 would transmit approximately 0.1% of all incident wavelengths of light through the material. Optical densities of OD-4, OD-5, OD-6, OD-7, OD-8, and OD-9 correspond to transmittal of approximately 0.01%, 0.001%, 0.0001%, 0.00001%, 0.000001%, and 0.0000001%, of incident wavelengths of light respectively. Optical density of a material associated with one or more wavelength ranges may be measured using a spectrophotometer.

[0053] As used herein, a layer of precursor material and / or a build surface may either be disposed directly on top of a build plate for a first layer of precursor material or it may be disposed indirectly on the build plate with one or more intervening layers of previously deposited precursor material disposed between the uppermost layer of precursor material and the build plate. Thus, it should be understood that the disclosure of a layer or build surface disposed on a build plate, or other components disposed on any underlying structure, may include both direct and / or indirect arrangements as the disclosure is not so limited.

[0054] It will be appreciated that any embodiments of the systems, components, methods, and / or programs disclosed herein, or any portion(s) thereof, may be used to formany part suitable for production using additive manufacturing. For example, a method for additively manufacturing one or more parts may, in addition to any other method steps disclosed herein, include the steps of selectively fusing one or more portions of a plurality of layers of precursor material deposited onto the build surface to form the one or more parts. This may be performed in a sequential manner where each layer of precursor material is deposited on the build surface and selected portions of the upper most layer of precursor material is fused to form the individual layers of the one or more parts. This process may be continued until the one or more parts are fully formed.

[0055] Turning to the figures, specific non-limiting embodiments are described in further detail. It should be understood that the various systems, components, features, and methods described relative to these embodiments may be used either individually and / or in any desired combination as the disclosure is not limited to only the specific embodiments described herein.

[0056] FIG. 1 shows, according to some embodiments, a schematic representation of an additive manufacturing system 100, including a plurality of laser energy sources 102 that deliver laser energy to an optics assembly 104 positioned within a machine enclosure 106. For example, the machine enclosure may define a build volume in which an additive manufacturing process may be carried out. In particular, the optics assembly may direct laser energy 108 towards a build surface 110 positioned within the machine enclosure to selectively fuse powdered material on the build surface. As described in more detail below, the optics assembly 104 may include a plurality of optics defining an optical path within the optics assembly that may transform, shape, and / or direct laser energy within the optics assembly such that the laser energy is directed onto the build surface as an array of laser energy pixels. In some embodiments, the optics assembly may be movable within machine enclosure 106 to scan laser energy 108 across build surface 110 during a manufacturing process. For example, the optics assembly may be associated with appropriate actuators, rails, motors, and / or any other appropriate structure capable of optics assembly relative to the surface. Alternatively, embodiments in which the optics assembly includes galvomirrors or other appropriate components that are configured to scan the laser energy 108 across the build surface while the optics assembly is held stationary relative to the build surface are also contemplated.

[0057] In some embodiments, the additive manufacturing system 100 further includes one or more optical fiber connectors 112 positioned between the laser energy sources 102 and the optics assembly 104. As illustrated, a first plurality of optical fibers 114 may extend between the plurality of laser energy sources 102 and the optical fiber connector 112. In particular, each laser energy source 102 may be coupled to the optical fiber connector 112 via a respective optical fiber 116 of the first plurality of optical fibers 114. Similarly, a second plurality of optical fibers 118 extends between the optical fiber connector 112 and the optics assembly 104. Each optical fiber 116 of the first plurality of optical fibers 114 is coupled to a corresponding optical fiber 120 of the second plurality of optical fibers 118 within the optical fiber connector. In this manner, laser energy from each of the laser energy sources 102 is delivered to the optics assembly 104 such that laser energy 108 can be directed onto the build surface 110 during an additive manufacturing process (i.e., a build process). Of course other methods of connecting the laser energy sources 100 due to the optics assembly 104 are also contemplated.

[0058] Fig. 2 depicts one embodiment of an additive manufacturing system at the beginning of a build process. The additive manufacturing system includes a build plate 202 mounted on a support plate 204, which is in turn mounted on one or more vertical supports 206 that attach to a base 208 (e.g., primary housing) of the additive manufacturing system. In the depicted embodiment, the one or more vertical supports may correspond to one, two, and / or any other appropriate number of supports configured to support the build plate, and the corresponding build surface, at a desired position and orientation. For example, the supports depicted in the figure may correspond to one or more vertical motion stages configured to control a vertical position and orientation of the build plate. A powder containment shroud 210 may at least partially, and in some embodiments completely, surround a perimeter of the build plate 202 to support a volume of precursor material 202a, such as a volume of powder, disposed on the build plate and contained within the shroud. An exposed upper surface of an upper most layer of the precursor material disposed on the build plate may form the build surface of the system that laser energy pixels may be directed onto to selectively fuse the precursor material. The shroud may be supported on the base 208 or by any other appropriate portion of the system.

[0059] The additive manufacturing system may include a powder deposition system in the form of a recoater 212 that is mounted on a first motion stage 214 that allows the recoater to be moved back and forth across either a portion, or entire, surface of the build plate 202. As the recoater traversers the build surface of the build plate, it deposits a precursor material 202a, such as a powder, onto the build plate and smooths the surface to provide a layer of precursor material with a predetermined thickness on top of the underlying volume of fused and / or unfused precursor material deposited during prior formation steps.

[0060] In some embodiments, the supports 206 of the build plate 202 may be used to index the build surface of the build plate 202 in a vertical downwards direction relative to a local direction of gravity. In such an embodiment, the recoater 212 may be held vertically stationary by the depicted horizontal motion stage for dispensing precursor material 202a, such as a precursor powder, onto the exposed build surface of the build plate as the recoater is moved across the build plate each time the build plate is indexed downwards.

[0061] In some embodiments, the additive manufacturing system may also include an optics assembly 218 that is supported vertically above and oriented downwards such that the optics assembly may be oriented towards the build plate 202 when it is disposed vertically above the build plate during operation. As detailed above, the optics assembly may be optically coupled to one or more laser energy sources, not depicted, to direct laser energy in the form or one or more laser energy pixels onto the build surface of the build plate 202. To facilitate movement of the laser energy pixels across the build surface, the optics assembly may be configured to move in one, two, or any number of directions in a plane parallel to the build surface of the build plate. To provide this functionality, the optics assembly may be mounted on a gantry, or other actuated structure, that allows the optics unit to be scanned in plane parallel to the build surface of the build plate.

[0062] As shown in Fig. 2, the recoater 212 and the optics assembly 218 may both be movably mounted on the first motion stage 214. As such, the first motion stage 214 may serve as a shared motion stage on which both the recoater 212 and the optics assembly 218 may independently move. The first motion stage 214 may be configured to allow the recoater 212 and the optics assembly 218 to move over the build plate 202 in a direction that is parallel to a longitudinal axis of the build plate 202. Accordingly, a motion plane of the recoater 212 and a motion plane of the optics assembly 218 may be substantially parallel in adirection that is parallel to the longitudinal axis of the build plate 202. The additive manufacturing system may also include a second motion stage, not shown, that allows the optics assembly 218 to move in a direction that is parallel to a transverse axis of the build plate 202. The transverse axis may be perpendicular to the longitudinal axis such that the optics assembly is able to move in two independent directions substantially parallel to an underlying build plate and / or build surface. The second motion stage may allow the optics assembly 218 to move in another direction (e.g., parallel to the transverse axis), thereby enabling the optics assembly 218 to scan across the build plate 202 and / or build surface 202a using these combined axes of motion.

[0063] In the above embodiment, the vertical motion stages, horizontal motion stages, and gantry may correspond to any appropriate type of motion stage as previously described. In addition, in some embodiments, the depicted additive manufacturing system may include one or more controllers 224 that is operatively coupled to the various actively controlled components of the additive manufacturing system. For example, the one or more controllers may be operatively coupled to the recoater 212, optics assembly 218, the various motion stages, and / or any other appropriate component of the system. In some embodiments, the controller may include one or more processors and associated non-transitory computer readable memory. The non-transitory computer readable memory may include processor executable instructions that when executed by the one or more processors cause the additive manufacturing system to perform any of the methods disclosed herein.

[0064] As previously introduced, focusing the laser energy sources with respect to the build surface of the additive manufacturing system may allow for proper spot sizes associated with the laser energy (e.g., laser energy pixels) during fusion and accordingly proper associated energy densities to be used for fusion. Focusing the laser energy sources may include aligning a focal plane associated with the laser energy sources with a plane parallel to the upper exposed portion of the precursor material. A laser energy source 302 according to some embodiments is shown in Fig. 3. The laser energy source 302 may direct a laser beam 304 having laser energy in a direction away from the laser energy source 302, or when included in an additive manufacturing system from a downstream portion of an associated optics assembly. The laser beam 304 may be directed towards a build surface as described herein, not shown in Fig. 3. The laser energy source 302 may have an associated focal plane308 disposed a distance F from the laser energy source. A portion of the laser beam 304 that is disposed the distance F from the laser energy source at the focal plane 308 may be in focus and may correspond to a waist of the laser energy beam. As such, operating the laser energy source 302 while the build surface is disposed approximately at the focal plane of the laser energy beam may provide a desired size, shape, and energy density of the corresponding laser energy pixels. However, as a location of a build surface changes along the length of the laser energy beam, the size and shape of the laser energy beam changes. For example, a plane 306 above the focal plane 308 and a bottom plane 310 disposed below the focal plane 308 are depicted and may correspond to threshold distances away from the focal plane 308 beyond which the laser energy beam may be considered to be out of focus. As will be discussed further, a pose of a plane of a build surface may be appropriately aligned relative to the focal planes of the laser energy sources of an additive manufacturing system such that the build surface may be positioned within a volume defined by a focal range of the laser energy sources and a motion plane of the optics assembly. For example, in some embodiments, a plane corresponding to a location of a build surface when one or more layers of precursor powder are disposed on a build plate may be positioned such that the build surface is within 0.5 mm, or other desired threshold for a particular system, of the focal plane. As such, a focal range may be -0.5 mm to 0.5 mm with respect to the position of the focal plane.

[0065] Figs. 4-6 show side views of an additive manufacturing system 400 including a recoater according to some embodiments. The recoater may include a recoater blade 410 coupled to a recoater bridge 408. The recoater bridge 408 may be coupled to a first linear stage 404 via a first adjustable mount 412. The recoater bridge 408 may also be coupled to a second motion stage 406 via a second adjustable mount 414 according to some embodiments. The corresponding directions of motion of the first motion stage 404 and the second motion stage 406 may be substantially parallel to one another. The first motion stage 404 and / or the second motion stage 406 may be coupled to any appropriate support members 416. A build plate 402 may be disposed underneath the recoater blade 410. The position of the recoater blade 410 may be adjusted vertically with respect to the build plate 402 from the perspectives of the views shown in Figs. 4-6 using the first adjustable mount 412 and / or the second adjustable mount 414. Thus, a position and / or orientation of an edge of the recoater blade 410 oriented towards and configured to contact a layer of precursor material during a scrapingprocess may be adjusted relative to a focal plane of an optics assembly such that the recoater blade may be disposed within a plane that is located within a focal range of the plurality of pixels during operation. This may include the adjustable mounts, and thus the recoater blade, being adjustable by a distance that is at least as great as a focal range of the laser energy sources.

[0066] As previously described, moving the recoater and the optics assembly on the same motion stage or set of motion stages (e.g., the first motion stage 404 and the second motion stage 406) may simplify aligning the motion plane of the recoater and the motion plane of the optics assembly. In some embodiments, the shared motion stage may be formed along a first axis of the build plate 402 which may be parallel to a longitudinal axis of the build plate. Accordingly, the need to align the motion plane of the recoater and the motion plane of the optics assembly relative to the longitudinal axis of the build plate in these embodiments may be reduced or eliminated. A second axis of the build plate 402 may be a transverse axis, which may be perpendicular to the longitudinal axis of the build plate. An orientation of a build surface formed due to motion of the recoater within the resulting motion plane of the recoater relative to the transverse axis of the build plate may be controlled by the orientation of the recoater blade 410 relative to the transverse axis of the build plate 402 which may extend in a direction that is approximately parallel to a longitudinal direction of the recoater. Thus, it may be desirable to align the recoater blade to have an orientation that is substantially parallel to a motion plane of the optics assembly and the recoater.

[0067] In view of the above, in some embodiments, the recoater blade 410 may be mounted to the recoater bridge 408 via a first adjustable mount 412 and a second adjustable mount 414. The adjustable mounts may enable a distance and orientation of the recoater blade 410 relative to the build plate 402 to be selectively adjusted. For example, an angle of the recoater blade 410 relative to the transverse axis of the build plate 402 may be selectively adjusted via the adjustable mounts and accordingly the orientation of the motion plane of the recoater relative to the transverse axis may be selectively adjusted. The vertical distance of the recoater blade 410 to the build plate 402 relative to a direction of gravity during use may also be selectively adjusted using the adjustable mounts. In some embodiments, the adjustable mounts may be adjusted such that the layer of precursor material formed by therecoater is proximate to the focal plane associated with the laser energy sources. For example, the adjustable mounts may be adjusted such that the recoater blade 410 forms a build surface in a plane that is disposed within a focal range of the focal plane associated with the laser energy sources. Accordingly, the resulting build surface may be within focus of the laser energy sources, and as such appropriate energy densities associated with the laser energy may be used to fuse the precursor material.

[0068] The adjustable mounts may include any appropriate adjustable mechanism configured to allow selective positioning of the recoater blade 410. For example, the adjustable mounts may include one or more height screws, piezo-electric actuators, piezo walk motors, voice coil actuators, any other appropriate actuator, any combination thereof, and any other appropriate adjustable mechanism. In embodiments where the adjustable mounts include height screws, the recoater blade 410 may be coupled to one or more height screws, and the height screws may be rotated to selectively adjust a vertical position of the recoater blade 410 relative to the build plate 402. For example, a first portion of the recoater blade 410 may be coupled to a first height screw of the first adjustable mount 412 and a second portion of the recoater blade may be coupled to a second height screw of the second adjustable mount 414 according to some embodiments. Of course, any construction and / or method of controlling the relative orientation and / or vertical position of the recoater blade 410 of a recoater may be used as the disclosure is not so limited.

[0069] As shown in Fig. 5A, the recoater blade 410 of a recoater may be positioned such that a portion of the recoater blade is outside of the focal range as defined by the top plane 306 and the bottom plane 310. As shown in Fig. 5A, a right portion of the recoater blade is disposed above the top plane 306 ad accordingly is outside of the focal range. As noted above, the focal range may be associated with one or more laser energy sources, such as one or more of the laser energy source 302 as shown and discussed with respect to Fig. 3. Using the first adjustable mount 412 and / or the second adjustable mount 414, the position of the recoater blade 410 may be changed, either manually or by one or more actuators, such that the a lower edge of the recoater blade that is scraped across a layer of precursor material during a scraping operation as the recoater is disposed within a plane that is disposed within the volume defined between the top and bottom focal planes 306 and 310 of the system. In the depicted embodiment of Fig. 5B, the recoater blade is positioned such that the entirelower edge of the recoater blade may be substantially aligned with the focal plane 308. Thus, the motion plane of the recoater blade when the recoater is scanned horizontally across the build surface may also be within the focal range.

[0070] Fig. 6A shows precursor material 422 disposed on the build plate 402. As described herein, the recoater may move in a horizontal direction substantially parallel to an upper surface of the build plate using one or more motion stages such as the depicted first motion stage 404 and second motion stage 406. This scrapes the recoater blade 410 across the upper layer of precursor material 422, thereby forming the build surface with the layer of precursor material. The resulting plane of the build surface may be substantially coplanar with the motion plane of the edge of the recoater blade oriented towards and in contact with the build surface during a scraping operation according to some embodiments. As shown in Fig. 6B, the recoater blade may form a substantially flat build surface on the build plate 402 with the precursor material 422. The resulting build surface may be substantially aligned with the focal plane 308 and / or may be within the volume formed by the focal range defined by the top plane 306 and the bottom plane 310. Accordingly, laser energy pixels directed onto the build surface may be in focus across an entire build surface in some embodiments.

[0071] Fig. 7 shows an additive manufacturing system 700 according to some embodiments. The additive manufacturing system 700 may include a build surface 702, where the build surface may be a limited portion of the dotted area shown in Fig. 7. An optics assembly 714 may be movably coupled to a gantry bridge 710, or other appropriate support structure, and the gantry bridge 710 may be movably coupled to a first motion stage 704 and a second motion stage 706. It should be understood that while a gantry bridge extending between two separate rails is depicted in the figures, it should be understood that any appropriate type of support capable of being attached to one or more motion stages may be used with any of the various embodiments of additive manufacturing system disclosed herein.

[0072] A recoater bridge 715, or other support structure for the recoater, may be movably coupled to the first motion stage 704 and the second motion stage 706. A recoater including a recoater blade 716 may be coupled to the recoater bridge 715 such that the recoater and optics assembly may both be mounted on one or more common motion stages. In the depicted embodiment of Fig. 7, the first motion stage 704 and the second motion stage 706 are formed as linear motion stages, aligned with a first movement axis 708, where thefirst movement axis is indicated with the set of arrows labeled 708. The first movement axis 708 may be parallel to a longitudinal direction of the build surface 702. As such, the gantry bridge 710 and the recoater bridge 715 may be configured to move linearly along the first motion stage 704 and the second motion stage 706 in a direction that is parallel to the first movement axis 708.

[0073] The optics assembly 714 may also be configured to move relative to the gantry bridge 710 along a second movement axis 712, where the second movement axis is indicated with the set of arrows labeled 712. In some embodiments, the second movement axis 712 may be parallel to a transverse direction of the build surface 702 and angled (e.g., perpendicular) relative to the first movement axis. For example, the optics assembly may be mounted on a third horizontal motion stage coupled to the gantry bridge 710, or other support structure, that is configured to move the optics assembly in a direction that is parallel to the indicated second movement axis. The third motion stage may include any of the supports, actuators, and movable components as described herein. For example, a motor may be configured to move the optics assembly 714 along the third motion stage, where the third motion stage includes at least one rail and linear bearings. In some embodiments, the third motion stage may include one or more actuators configured to move the optics assembly 714 vertically relative to the build surface 702.

[0074] The first motion stage 704, second motion stage 706, gantry bridge 710, and / or any actuators as described herein may include any appropriate sensors configured to sense positions associated with elements movably coupled to the motion stage, such as the recoater bridge 715, gantry bridge 710, and optics assembly 714. The position may be sensed using one or more encoders, angular position sensors, magnetic sensors, potentiometers, linear variable differential transformer (LVDT), any combination thereof, and any other appropriate sensor configured to measure position as the disclosure is not so limited. The position signals of the various motion stages may be transmitted to one or more associated controllers, which may include one or more processors, that are configured to control motion of the various motion stages based at least in part on the received position signals. As described herein, the first motion stage 706 and the second motion stage 708 may include any appropriate actuators and any appropriate position sensors configured to sense a position of the recoater bridge 715 and / or the gantry bridge 710. For example, in some embodiments, thefirst motion stage 704 and / or the second motion stage 706 may include any of the aforementioned position sensors, such as one or more encoders configured to determine the position of the gantry bridge 710 and / or the recoater bridge 715 along the one or more motion stages such that an absolute and / or relative position of the recoater and optics assembly may be sensed. The positions sensed by the position sensors may be obtained by any of the controllers described herein and the movement of the recoater bridge, gantry bridge, and / or optics assembly may be controlled based at least in part on the obtained positions.

[0075] Movement of the recoater bridge 715 (and the recoater blade 176 coupled thereto) and the optics assembly 714 may be controlled / coordinated during operation of the additive manufacturing system 700 to avoid collisions and / or contact between the recoater bridge 715 and the optics assembly 714. While the layer of precursor material is being formed on the build plate 702 by the recoater (e.g., during a recoating mode of operation of the additive manufacturing system), the optics assembly 714 may be moved such that the optics assembly does not contact the recoater bridge 710 or the recoater blade 716. For example, the optics assembly 714 may be moved to an optics assembly park area 718, and the recoater may be controlled to prevent movement into the optics assembly park area 718 to avoid contact with the optics assembly 714 during the formation of the layer of precursor material. Similarly, while laser energy is directed towards the build plate 702 from the optics assembly 714 (e.g., during a fusing mode of operation of the additive manufacturing system), the recoater and optics assembly 714 may be controlled to avoid contact between any portion of the recoater and the optics assembly 714. For example, the recoater bridge 715 and the recoater blade 716 may be moved to a recoater park area 720 and the optics assembly 714 may be controlled to prevent movement of the optics assembly 714 into the recoater park area 720 along the combined motion stage (e.g., one or both of the first motion stage 704 and the second motion stage 706). In one embodiment, the recoater park area and the optics assembly park area may correspond to portions of the one or more common motion stages shared by the recoater and optics assembly that are disposed on opposing sides of the build plate as illustrated in the figures.

[0076] As introduced above, the recoater and the optics assembly may have park areas according to some embodiments. The park areas may allow for the recoater and the optics assembly to perform their respective functions as described herein without colliding orotherwise contacting one another, or any other portion of the additive manufacturing system 700. As such, the park areas may prevent damage to the recoater and optics assembly, as well as other portions of the additive manufacturing system. For example, in the depicted embodiment of Fig. 7, the recoater bridge 715 may travel along the first motion stage 704 and the second motion stage 706 to a recoater park area 720. While the recoater (e.g., the recoater bridge 715 and the recoater blade 716) are disposed in the recoater park area 720, the optics assembly 714 may be moved over the build surface 702 to fuse material. The optics assembly 714 may also be moved to an optics assembly park area 718 by moving the gantry bridge 710 along the first motion stage 704 and the second motion stage 706 to the optics assembly park area 718. Both the recoater park area 720 and the optics assembly park area 718 may be disposed outside of the build surface 702 and may be appropriately sized and shaped to accommodate the recoater or optics assembly respectively when positioned within the corresponding parking area. It should be understood that the above noted position sensors may be used at least in part to control positioning of the recoater and optics assembly along the common motion stage to coordinate movement of these components during operation to provide the above described operation.

[0077] The additive manufacturing system 700 may include one or more proximity sensors 722 configured to detect collisions or any form of contact between two or more portions of the additive manufacturing system 700. For example, in the depicted embodiment of Fig. 7, a proximity sensor 722 is coupled to the optics assembly (e.g., gantry bridge 710) and may be configured to detect contact between and / or close proximity within a threshold distance of the recoater (e.g., the recoater bridge 715) and the optics assembly as they are located on a common motion stage. The one or more proximity sensors 722 or any other appropriate sensor may be configured to detect contact or close proximity of an object may be coupled to the recoater bridge 715, optics assembly 714, the secondary housing, the primary housing, combinations of the above and any other appropriate portions of the additive manufacturing system 700 that may come into contact with one another. Any appropriate proximity sensors may be used herein, including but not limited to inductive proximity sensors, Hall effect sensors (e.g., a magnet mounted on one structure and a Hall sensor mounted on the other structure), capacity proximity sensors, magnetic reed switches, contact switches, and appropriate combination thereof, and any other appropriate sensor orsensors that are configured to sense when structures associated with the recoater and optics assembly are within a threshold distance of each other. The proximity sensors may optionally include a damper such as a dashpot configured to dissipate forces associated with any crashes or other contact which may occur on the proximity sensor. The proximity sensors 722 may be operatively coupled to any appropriate controller described herein, and the controller may be configured to obtain sensor data from the proximity sensors 722. The controller may control any appropriate portion of the additive manufacturing system 700 based at least in part on the obtained sensor data. For example, when a proximity sensor senses that a recoater and optics assembly are within a threshold distance of each other, the one or more controllers of a system may stop operation of the one or more associated motion stages in an attempt to prevent contact between these components. Thus, the motion stage(s) of the optics assembly and recoater may be controlled base at least in part on a signal received from the one or more proximity sensors during operation of the system.

[0078] In some embodiments, the proximity sensors 722 may include an inductive proximity sensor disposed on a structure with sufficient strength to absorb the force associated with an impact of the crash / contact, see Fig. 12. For example, one or more proximity sensors 1206 associated with a recoater and / or optics assembly may be configured to detect the proximity of a component within the movement path to the proximity sensor. This may include an inductive sensor, magnetic sensor, or other sensor including parts disposed on the two separate components that are being monitored such that when the components are brought within a threshold distance relative to each other, their approximated positions may be sensed by the sensor. Alternatively, a distance sensor may be used to measure a distance between the recoater, optics assembly, or other components. In the depicted embodiment, a first portion of the sensor is disposed on a standoff 1204 which may be coupled to a reinforced portion 1200 of a second component 1208 which may be configured to contact against a portion of the first component 1206. In instances where inductive or magnetic sensors are used, the different portions of the sensors may be associated with these different components such that a signal may be detected when the components are brought into proximity with one another. Thus, an associated controller, including one or more processors, may control the first and second stators 1109 associatedwith the separate components to stop motion of the components in an attempt to avoid a collision.

[0079] In the instance in which a crash, or other contact may occur between a recoater and optics assembly, it may be desirable to mitigate damage associated with such contact. Thus, in some embodiments, the system may include one or more dashpots, or other appropriate dampers 1202, disposed on one or both components (e.g., the recoater and / or optics assembly) such that when a standoff 1204 contacts the other portion, it may compress an associated damper 1202 which may absorb some of the impact energy rather than transmitting the impact energy into the components.

[0080] Fig 8 shows an additive manufacturing system 800 according to some embodiments. The additive manufacturing system 800 may include a first motion stage 804 and a second motion stage 806. A gantry bridge 810 and a recoater bridge 816, or other appropriate supports moveably coupled to the associated motion stages, may be movably coupled to the first motion stage 804 and the second motion stage 806 and may be configured to move the optics assembly 814 and recoater 809, and the associated recoater blade 809a, along the first motion stage 804 and the second motion stage 806 in a direction that is parallel to the build surface and a first motion axis 808. As the optics assembly and the recoater are both mounted on these common motion stages, the motion planes of the recoater and optics assembly in this direction may be substantially parallel to one another. The optics assembly 814 may also movably coupled to the gantry bridge 810 via a third motion stage 826 that may be configured to move in a direction that is parallel to a second movement axis 812 that may be perpendicular to the first movement axis. Therefore, the optics assembly 814 may be scanned across the various portions of the build surface disposed on the underlying build plate.

[0081] In some embodiments, the additive manufacturing system 800 may include magnetic tracks extending along the first motion stage 808 and the second motion stage 807. The magnetic tracks may optionally extend in a direction parallel to the first axis of the build plate. One or more stators may be coupled to any appropriate movable element (e.g., recoater bridge 816 and / or optics assembly 814) of the additive manufacturing system 800 and may be configured to receive an electrical current. The electrical current may cause the stator and the magnetic track to form magnetic forces which may move the stator and any element (e.g.,recoater, recoater bridge 816, gantry bridge 810, and / or optics assembly 814) attached thereto to move along the motion stage. In some embodiments, the magnetic tracks may extend in the direction parallel to a first movement axis 808 of the build plate as described herein. The inventors have recognized the that sharing a magnetic track to move both the recoater and the optics assembly may present the additional benefit cost savings, especially when expensive magnetic tracks are used. Thus, one or more combined linear motors may be used to drive both the recoater and optics assembly along one or more common magnetic tracks where the recoater and optics assembly may both include one or more separate stators configured to independently drive the recoater bridge 816 and optics assembly 814 along the one or more common magnetic tracks. For example, by using a first stator coupled to the optics assembly and a second stator coupled to the recoater, one or more common magnetic tracks may be used to independently control motion of the recoater and optics assembly when separately controlled electrical currents, or other measure of power, are applied to the separate stators to cause the stators and associate recoater and / or optics assembly to move along the depicted motion stage.

[0082] Following from the above, the additive manufacturing system 800 may include a first magnetic track 805 and a second magnetic track 807. In the depicted embodiment of Fig. 8, the first magnetic track 805 and the second magnetic track 807 extend along the build surface in a direction that is parallel to the first movement axis 808. One or more stators 809 may be coupled to the gantry bridge 810 and the recoater bridge 816 and may be configured to receive electrical current. Upon receiving the electrical current, the stators 809 and the magnetic tracks 805 and 807 may form magnetic forces that move the stators 809 along the first motion stage 804 and the second motion stage 806. In some embodiments, the stators 809 may be movably coupled to the first motion stage and / or the second motion stage via any appropriate movable component. For example, the stators 809 may be movably coupled to the motion stages via rails and ball bearings.

[0083] Similar to the park areas described with respect to Fig. 7, the additive manufacturing system 800 may include a recoater park area 820 and an optics assembly park area 818. The recoater bridge 816 and any recoater blade attached thereto may be moved to the recoater park area 820, which may be disposed outside of the build surface area 802. Thegantry bridge 810 and the optics assembly coupled thereto may be moved to the optics assembly park area 818, which may also be disposed outside of the build surface 802.

[0084] The additive manufacturing system 800 may include a controller 822 which may be operatively coupled to any appropriate portion of the additive manufacturing system 800, including the stators 809, optics assembly 814, recoater bridge 816, and any other appropriate portion of the additive manufacturing system 800. The controller 822 may be configured to control any of the aforementioned portions of the additive manufacturing system 800 according to some embodiments. A power source 824 may be coupled to the controller 822 and may be configured to provide power to the controller 822 and any other appropriate portion of the additive manufacturing system 800.

[0085] A method for additive manufacturing 900 will be described with regard to Fig.9 herein with reference to Fig. 8. It should be understood however, that while the method 900 will be described herein with respect to Fig. 8, the method 900 may be used with any of the additive manufacturing systems and methods described herein, including the embodiments depicted by Figs. 1-7 and 10-11 and any other appropriate embodiment as the disclosure is not so limited. At 902, an optics assembly may be moved in a direction that is parallel to a first movement axis of a build surface using at least one motion stage. For example, the gantry bridge 810 with the optics assembly 814 coupled thereto may be moved along at least of the first motion stage 804 and / or the second motion stage 806 in a direction parallel to the first movement axis 808 to be disposed over the build surface 802. At 904, the optics assembly may be moved in a direction that is parallel to a second movement axis of the build surface using at least one transverse motion stage. For example, the optics assembly 814 may be moved along the gantry bridge 810 in a direction parallel to the second movement axis 812 to any appropriate position over the build surface 802.

[0086] Laser energy may be directed from one or more laser energy sources through the optics assembly and towards the build surface, see 906. For example, laser energy may be directed through the optics assembly 814 towards the build surface 802. At 908, precursor material disposed on the build surface may be fused to form a fused material layer. For example, precursor material powder disposed on the build surface 802 may be fused to form a layer of part being built. At 910, the optics assembly may be moved in a direction parallel to the first axis using the at least one motion stage to an optics assembly park area. For example,the gantry bridge 810 and the optics assembly 814 coupled thereto may be moved in a direction parallel to the first movement axis 808 along at least one of the first motion stage 804 and the second motion stage 806 to the optics assembly park area 818. At 912, after the optics assembly is in the parked configuration, a recoater may be moved along a motion stage that is in common with the optics assembly such that the recoater is moved in a direction that is substantially parallel to the first axis using the at least one motion stage to recoat the build surface with a layer of precursor material. For example, the recoater bridge 816 and the recoater blade attached thereto may be moved in a direction parallel to the first movement axis 808 along one or both of the first motion stage 804 and the second motion stage 806 to the form the layer of precursor material on the build surface 802. Thus, the motion plane of the recoater and the motion plane of the optics assembly may be substantially parallel to one another through this movement of both components along one or more shared motion stages. At 914, the recoater may be moved along the first axis using the at least one motion stage to a recoater park area. For example, the recoater bridge 816 and the recoater blade attached thereto may be moved in a direction parallel to the first axis of movement 808 along at least one of the first motion stage 804 and the second motion stage 806 to the recoater park area 820. The method 900 may repeat 902-914 until part formation is complete, iteratively fusing and recoating layers of precursor material until the final layer is fused and the part is entirely formed. At 916, if the part formation is not complete, the method may perform 902-914 again. Also at 916, if the part formation is complete, the method 900 may end at 918.

[0087] The above method may be implemented by one or more controllers including at least one processor operatively coupled to the various controllable portions of an additive manufacturing system as disclosed herein. The method may be embodied as computer readable instructions stored on non-transitory computer readable memory associated with the at least one processor such that when executed by the at least one processor the additive manufacturing system may perform any of the actions related to the methods disclosed herein. Additionally, it should be understood that the disclosed order of the steps is exemplary and that the disclosed steps may be performed in a different order, simultaneously, and / or may include one or more additional intermediate steps not shown as the disclosure is not so limited.

[0088] As previously discussed, an interior volume of an additive manufacturing system may include an inert atmosphere. Costs associated with forming and maintaining an inert atmosphere may be reduced by reducing the amount of inert gas used to form and maintain the inert atmosphere. Reducing the inert gas used may be accomplished by reducing the volume of the interior volume and / or by reducing leakage of the inert gas from the atmosphere of the interior volume. As such, the secondary housing may be formed with a reduced volume to reduce (e.g., minimize) the inert gas used to form an inert atmosphere and the secondary housing and the primary housing may be coupled and sealed to reduce leakage of inert gas. Generally, the primary housing may house the bottom portion of the additive manufacturing system and the secondary housing may house the upper portion of the additive manufacturing system. The upper portion may be disposed vertically above the lower portion relative to a direction of gravity and may include the optics assembly, recoater, associated motion stages, and other appropriate portions of the additive manufacturing system as shown in Fig. 10. The secondary housing may be coupled to the primary housing by positioning the secondary housing on and sealing the secondary housing with the primary housing.

[0089] In the depicted embodiment of Fig. 10, the additive manufacturing system 1000 may include a base, which may be formed as a primary housing 208, and a secondary housing 1002 coupled thereto. The primary housing and the secondary housing may form an interior volume 1031, where the interior volume may be sealed. The interior volume 1031 may include an atmosphere, which may be an inert atmosphere as previously discussed. The base 208 may house a lower portion of the additive manufacturing system 1000 and the secondary housing 1002 may house an upper portion of the additive manufacturing system 1000. The secondary housing 1002 is indicated in Fig. 10 with the dashed-dotted line. The secondary housing may couple to any appropriate portion of the base 208, and optionally may be removable so operators may access the upper portion of the additive manufacturing system 1000. While the secondary housing 1002 is represented with a rectangular-like geometry, the secondary housing 1002 may be formed in any appropriate geometry as the disclosure is not limited to the geometry of the secondary housing whatsoever. For example, the secondary housing 1002 may be formed with any appropriate shape or geometric features including rounds surfaces / edges. This ability to form complex shapes of the secondary housing may help to at least partially conform a size and shape of the secondary housing to the componentslocated within an upper portion of the system. Again, this may help to reduce and overall volume of the sealed interior volume of the system while helping to avoid the use of additional seals.

[0090] The primary housing 208 may include an integrally formed frame according to some embodiments. In some embodiments, the integrally formed frame may be a mineral cast frame. An integrally formed mineral cast frame may provide sufficient structural support while reducing leakage associated with the atmosphere of the interior volume 1031. The primary housing 208 may include any appropriate access ports (e.g., openings with associated movable panels and / or doors) to enable access to any appropriate portions of the lower portion of the additive manufacturing system 1000. The primary housing 208 may include one or more seals formed at any of the access ports. The access ports of the primary housing 208 may include any appropriate seal configured to help maintain the atmosphere of the interior volume 1031. For example, the primary housing 208 may include one or more gland seals. Of course, while a mineral cast frame with associated seals and panels may be advantageous, in some embodiments, other types of housing constructions such as frame and panel construction with appropriate seals may also be used as the disclosure is not so limited.

[0091] The joining of the primary housing 208, which may contain the lower portion of the system, and the secondary housing 1002, which may contain the upper portion of the system, may be sealed as described herein. Joining the primary housing and the secondary housing may involve positioning a portion of the secondary housing proximate to a portion of the primary housing and securing the portion of the secondary housing to the portion of the primary housing. In some embodiments, securing the secondary housing to the primary housing may involve using one or more permanent or removable fasteners to removably fasten the secondary housing to the primary housing. For example, one or more bolts or any other appropriate fasteners may be configured to secure the secondary housing to the primary housing. In some embodiments, the primary housing and / or secondary housing may include any appropriate seal material configured such that when the secondary housing is secured to the primary housing, a seal (e.g., a gas tight seal) is formed. As described herein, when the interior volume is sealed, an atmosphere of the interior volume may be substantially isolated from the surrounding atmospheres. In some embodiments, a seal may extend along each portion of the secondary housing 1002 that contacts the primary housing 208 and may beconfigured to form a seal between the secondary housing 1002 and the primary housing 208. The seals as described herein may be any appropriate seal or combination of seals. In some embodiments, the seals may include one or more gasket seals, gland seals, split seals, gland seals, labyrinth seals, ferrofluidic seals, pusher seals, any combination thereof, and any other appropriate type of seal as the disclosure is not limited to any type or quantity of seals. In some embodiments, a portion of the secondary housing configured to be proximate to the primary housing may have a surface

[0092] Laser energy beams 1004 (indicated with two dashed lines) are shown being emitted from the optics assembly 218 and directed towards the build plate 202 and / or build surface 202a. Laser energy from the laser energy beams 1004 may melt and fuse precursor material on the build plate 202 as described herein and may create reflected laser energy 1006 (indicated with two arrows with dotted lines). As previously described, the secondary housing 1002 may be formed to be opaque to laser energy reflected from the build surface. As such, the reflected laser energy 1006 is shown as being incident on the secondary housing 1002, and being blocked (e.g., not transmitted) by the secondary housing 1002 due to the secondary housing being made with a composite material exhibiting sufficient optical density of the laser energy to reduce an intensity of laser energy transmitted through the secondary housing to be less than a desired threshold which may be equal or less than to a maximum permitted exposure limit as defined by an appropriate industry standard (e.g., maximum permitted exposure as described by ANSI Z136.1). The transmitted light energy and absorbance of a material and system may be determined using spectrophotometers, the methods disclosed in ANSI Z136.1, and / or any other appropriate method.

[0093] During operation of the additive manufacturing systems and methods disclosed herein, particles from the build surface may be generated within (e.g., by wear of moving components), emitted into (e.g., by dispensing of a powder precursor material, contaminants and gasses emitted during a fusing process, etc.), or otherwise dispersed within the interior volume of a system such that these contaminants may become airborne within the interior volume. For example, during fusion and / or recoating, material particles from the layer of precursor material may be agitated and may travel through the atmosphere of the interior volume. For example, airborne particles may be generated at the welding surface as a result of energy applied by the laser energy. The particles may travel to and become disposedon movable portions of the additive manufacturing system, presenting opportunity to prevent movement and / or damage various portions of the additive manufacturing system. For example, powder particles may enter bearings, rails, or other moveable portions of a motion stage which may cause friction and / or potentially prevent or interfere with movement of, for example, the recoater and / or optics assembly. As such, the inventors have recognized that it is desirable to filter the atmosphere within the interior volume. In some embodiments, this may include directing one or more flows of gas (e.g., crossflows) through the interior volume to remove particles from within the interior volume for filtering prior to their depositing onto components that may interfere with operation of the additive manufacturing system. One such embodiment of an additive manufacturing system 1000 is shown in Figs. 10 and 11.

[0094] In the depicted embodiment, the one or more flows of gas may be configured to form a crossflow of gas in an interior volume 1031. A secondary housing 1002 may include at least one inlet and at least one outlet, and the flow of gas may be directed to enter the interior volume 1031 through an inlet and exit the interior volume through an outlet. In some embodiments, the secondary housing may include a plurality of inlets and outlets and associated pathways and pumps. For example, the secondary housing may include two or more inlets and outlets, and two or more associated pathways and pumps configured to direct two or more flows of gas through the interior volume, see Fig. 11. The pathways may include any appropriate one or more filters 1028 disposed along the depicted flow paths that are configured to filter the flows of gas, and the pathways may include any appropriate quantity of filters disposed in any appropriate portion of the pathways as the disclosure is not so limited. Thus, the flow of gas including particles entrained in the atmosphere of the internal volume of the system may flow out of the interior volume and through one or more associated filters. In some embodiments, the one or more filters 1028 may be configured to filter (e.g., remove) particulates from the flow of gas. In some embodiments, the pathways may be fluidly coupled to a gas source such as an inert gas source and may be configured to direct a flow of gas from the gas source into the interior volume 1031. The volumetric flowrate of the crossflow may be selected depending on a number of factors including the precursor material being used, the speed of fusion, a number of gas volume turnovers per time period are desired, and / or any other appropriate factor associated with the additivemanufacturing system. In some embodiments, the volumetric flow rate of the crossflow may be selectively controlled using the one or more pumps 1026.

[0095] In some embodiments, the volumetric flow rate of the crossflow in the interior volume may be less than or equal to approximately 0.250 m3 / s, 0.225 m3 / s, 0.200 m3 / s, 0.175 m3 / s, 0.150 m3 / s, and / or any other appropriate volumetric flow rate. The volumetric flow rate of the crossflow in the interior volume may also be greater than or equal to 0.150 m3 / s, 0.175 m3 / s, 0.200 m3 / s, 0.225 m3 / s, 0.250 m3 / s, and / or any other volumetric flow rate.Combinations of the foregoing, including volumetric flow rates between or equal to 0.150 m3 / s and 0.250 m3 / s are also contemplated, as well as volumetric flow rates above and below the ranges listed above, as the present disclosure is not limited by the volumetric flow rate of the crossflow in the interior volume. In either case, the volumetric flow rate may be selected such that a volume of gas equal to a volume of the interior volume of an additive manufacturing system may be filtered at least once every

[0096] As discussed above, material particles suspended / traveling within the interior volume 1031 may damage or interfere with portions of the additive manufacturing system 1000, including any of the motion stages described herein. As such, the material particles may be directed to exit the interior volume 1031 using one or more flows of gas through the secondary housing 1002 to avoid damage or interference any portions of the additive manufacturing system 1000. The secondary housing 1002 may include a first inlet 1030 fluidly coupled to the interior volume 1031 and a first pathway 1033. The secondary housing may also include a first outlet 1032 fluidly coupled to the interior volume 1031 and the first pathway 1033. To help facilitate flow of gas and contaminants out of the interior volume, it may be desirable to position the one or more inlets 1030 and outlets 1032 for the gas filtration system on opposing sides of an internal volume 1031 of the system and vertically above (relative to a direction of gravity) the associated optics assembly 218, recoater 212, and associated motion stages. This may include positioning the depicted inlet and outlet in the secondary housing 1002 on opposing sides of the build plate in a first direction (e.g., a width direction) and offsetting the inlet and outlet from one another in a second direction (e.g., a length direction) of the build plate. Again, this may help to create a cross flow across the internal volume both in a width and length direction of the volume that may help to removecontaminants from the volume while also helping to avoid stagnation points within the volume.

[0097] A pump 1026 may be fluidly coupled to the inlet 1030, interior volume 1031, outlet 1032, and fluid pathway 1033, and may be configured to direct a flow of gas through the interior volume 1031 from the inlet 1030 to the outlet 1032. The flow of gas may form a crossflow and may travel through the outlet 1032 into the fluid pathway 1033. The fluid pathway may include a filter 1028 configured to filter the flow of gas traveling through the fluid pathway. The pump 1026 may be controlled at least in part using the controller 1022, or any other appropriate controller as discussed herein, and may be powered using the power source 1024.

[0098] The additive manufacturing system may include any appropriate number of inlets, outlets, and flows of gas. For example, in the embodiment shown in Fig. 11, an additive manufacturing system 1100 includes a first inlet 1134 and first outlet 1136 as well as a second inlet 1130 and second outlet 1132, where the first inlet and outlet may be associated with a first flow of gas and the second inlet and outlet may be associated with a second flow of gas. The first inlet 1134 may be fluidly coupled to an interior volume 1131, which may be formed at least in part by a secondary housing 1129 as described herein, and a first pathway 1137. The interior volume 1131 may also be formed at least in part with a primary housing, not shown in the depicted embodiment of Fig. 11, as previously described. The first outlet1136 may be fluidly coupled to the interior volume 1131 and the first pathway 1137. A pump 1126 may be fluidly coupled to the first inlet 1134, interior volume 1131, first outlet 1136, and first fluid pathway 1137, and may be configured to direct a flow of gas through the interior volume 1131 from the first inlet 1134 to the first outlet 1136. The flow of gas may travel through the first outlet 1136 into the first fluid pathway 1137. The first fluid pathway1137 may include a filter 1128 configured to filter the flow of gas traveling through the first fluid pathway.

[0099] The second inlet 1130 may be fluidly coupled to the interior volume 1131 and a second pathway 1133. The second outlet 1132 may be fluidly coupled to the interior volume 1131 and the second pathway 1133. A pump 1126 may be fluidly coupled to the second inlet 1130, interior volume 1131, second outlet 1132, and second fluid pathway 1133, and may be configured to direct a flow of gas through the interior volume 1131 from thesecond inlet 1130 to the second outlet 1132. The flow of gas may travel through the second outlet 1132 into the second fluid pathway 1133. The second fluid pathway 1133 may include a filter 1128 configured to filter the flow of gas traveling through the second fluid pathway. The first pathway and second pathway as described herein with regard to Fig. 10-11, and any other appropriate embodiments, may be formed using any appropriate conduit, tubing, piping, valves, or other elements configured to direct a flow of gas as the disclosure is not so limited. Also, it should be understood that any of the filters described herein, including but not limited to those discussed with respect to Figs. 10 and 11, may be positioned in any appropriate position along the pathways, interior volume, inlets, and / or outlets as the disclosure is not limited in this fashion. For example, the filters may be positioned proximal to the outlets such that gas exiting the interior volume may be filtered, or any other appropriate position.

[0100] In some embodiments, the respective inlets and outlets of the secondary housing where flows of gas enter and exit the interior volume may be disposed on opposing sides of the secondary housing, as shown in the depicted embodiment on Figs. 10 and 11. An inlet and associated outlet may also be formed offset relative to one another along the first or second (e.g., longitudinal or transverse) axis of the build plate and / or build surface, such as the inlets and outlets shown in the depicted embodiment of Fig. 11. Forming the inlet and the outlet offset from one another may help to increase the circulation of gas within the interior volume, thereby helping to direct an increased quantity of material particles within the interior volume to one or more outlets. Including a plurality of inlets and outlets and associated flows of gas may be useful to increase the quantity and / or speed of material particles exiting the interior volume. In some embodiments, the flows of gas traveling through the pathways may be filtered and may be directed to reenter the interior volume, thereby recirculating the flows of gas to continue removing material particles from the interior volume.

[0101] The above-described embodiments of the technology described herein can be implemented in any of numerous ways. For example, the embodiments may be implemented using hardware, software or a combination thereof. When implemented in software, the software code can be executed on any suitable processor or collection of processors, whether provided in a single computing device or distributed among multiple computing devices. Such processors may be implemented as integrated circuits, with one or more processors inan integrated circuit component, including commercially available integrated circuit components known in the art by names such as CPU chips, GPU chips, microprocessor, microcontroller, or co-processor. Alternatively, a processor may be implemented in custom circuitry, such as an ASIC, or semicustom circuitry resulting from configuring a programmable logic device. As yet a further alternative, a processor may be a portion of a larger circuit or semiconductor device, whether commercially available, semi-custom or custom. As a specific example, some commercially available microprocessors have multiple cores such that one or a subset of those cores may constitute a processor. Though, a processor may be implemented using circuitry in any suitable format.

[0102] Further, it should be appreciated that a computing device including one or more processors may be embodied in any of a number of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Additionally, a computing device may be embedded in a device not generally regarded as a computing device but with suitable processing capabilities, including a Personal Digital Assistant (PDA), a smart phone, tablet, or any other suitable portable or fixed electronic device.

[0103] Also, a computing device may have one or more input and output devices. These devices can be used, among other things, to present a user interface. Examples of output devices that can be used to provide a user interface include display screens for visual presentation of output and speakers or other sound generating devices for audible presentation of output. Examples of input devices that can be used for a user interface include keyboards, individual buttons, and pointing devices, such as mice, touch pads, and digitizing tablets. As another example, a computing device may receive input information through speech recognition or in other audible format.

[0104] Such computing devices may be interconnected by one or more networks in any suitable form, including as a local area network or a wide area network, such as an enterprise network or the Internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol and may include wireless networks, wired networks or fiber optic networks.

[0105] Also, the various methods or processes outlined herein may be coded as software that is executable on one or more processors that employ any one of a variety of operating systems or platforms. Additionally, such software may be written using any of anumber of suitable programming languages and / or programming or scripting tools, and also may be compiled as executable machine language code or intermediate code that is executed on a framework or virtual machine.

[0106] In this respect, the embodiments described herein may be embodied as a computer readable storage medium (or multiple computer readable media) (e.g., a computer memory, one or more floppy discs, compact discs (CD), optical discs, digital video disks (DVD), magnetic tapes, flash memories, RAM, ROM, EEPROM, circuit configurations in Field Programmable Gate Arrays or other semiconductor devices, or other tangible computer storage medium) encoded with one or more programs that, when executed on one or more computers or other processors, perform methods that implement the various embodiments discussed above. As is apparent from the foregoing examples, a computer readable storage medium may retain information for a sufficient time to provide computer-executable instructions in a non-transitory form. Such a computer readable storage medium or media can be transportable, such that the program or programs stored thereon can be loaded onto one or more different computing devices or other processors to implement various aspects of the present disclosure as discussed above. As used herein, the term "computer-readable storage medium" encompasses only a non-transitory computer-readable medium that can be considered to be a manufacture (i.e., article of manufacture) or a machine. Alternatively or additionally, the disclosure may be embodied as a computer readable medium other than a computer-readable storage medium, such as a propagating signal.

[0107] The terms “program” or “software” are used herein in a generic sense to refer to any type of computer code or set of computer-executable instructions that can be employed to program a computing device or other processor to implement various aspects of the present disclosure as discussed above. Additionally, it should be appreciated that according to one aspect of this embodiment, one or more computer programs that when executed perform methods of the present disclosure need not reside on a single computing device or processor, but may be distributed in a modular fashion amongst a number of different computers or processors to implement various aspects of the present disclosure.

[0108] Computer-executable instructions may be in many forms, such as program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particulartasks or implement particular abstract data types. Typically the functionality of the program modules may be combined or distributed as desired in various embodiments.

[0109] The embodiments described herein may be embodied as a method, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

[0110] Further, some actions are described as taken by a “user.” It should be appreciated that a “user” need not be a single individual, and that in some embodiments, actions attributable to a “user” may be performed by a team of individuals and / or an individual in combination with computer-assisted tools or other mechanisms.

[0111] While the present teachings have been described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments or examples. On the contrary, the present teachings encompass various alternatives, modifications, and equivalents, as will be appreciated by those of skill in the art. Accordingly, the foregoing description and drawings are by way of example only.

Claims

CLAIMS1. An additive manufacturing system comprising: a first motion stage extending in a direction that is parallel to a first axis of a build plate of the additive manufacturing system; a recoater movably coupled to the first motion stage, wherein the recoater is configured to move along the first motion stage relative to the build plate and parallel to the first axis, and wherein the recoater is configured to form a layer of precursor material disposed on the build plate; one or more laser energy sources; and an optics assembly movably coupled to the first motion stage, wherein the optics assembly is configured to move along the first motion stage relative to the build plate and parallel to the first axis, and wherein the optics assembly is configured to direct laser energy from the one or more laser energy sources toward the build plate to melt at least a portion of the layer of precursor material disposed on the build plate.

2. The additive manufacturing system of claim 1, wherein the first motion stage is a first linear motion stage, and wherein the recoater and the optics assembly are both configured to move linearly along the first linear motion stage.

3. The additive manufacturing system of any of the preceding claims, further comprising: a magnetic track extending along the first motion stage in the direction parallel to the first axis of the build plate; a first stator coupled to the optics assembly, wherein the first stator is configured to receive an electrical current, and wherein when the first stator receives the electrical current, the first stator and the magnetic track form magnetic forces which cause the first stator and the optics assembly to move along the first motion stage; and a second stator coupled to the recoater, wherein the second stator is configured to receive an electrical current, and wherein when the second stator receives the electrical current, the second stator and the magnetic track form magnetic forceswhich cause the second stator and the optics assembly to move along the first motion stage.

4. The additive manufacturing system of any of the preceding claims, further comprising a second motion stage extending in a direction that is parallel to a second axis of a build plate of the additive manufacturing system, wherein the second axis is perpendicular to the first axis, and wherein the optics assembly is movably coupled to the second motion stage, and wherein the optics assembly is configured to move along the second motion stage relative to the build plate and parallel to the second axis.

5. The additive manufacturing system of any of the preceding claims, wherein the first motion stage includes opposing rails disposed on opposing sides of the build plate, wherein the optics assembly is movably coupled to the opposing rails, wherein the optics assembly is configured to move along the opposing rails relative to the build plate along the first axis, and wherein the recoater is movably coupled to the opposing rails, wherein the recoater is configured to move along the opposing rails relative to the build plate and parallel to the first axis.

6. The additive manufacturing system of any of the preceding claims, wherein the recoater comprises a recoater blade mounted to the recoater via adjustable mounts, wherein a distance and orientation of the recoater blade relative to the build plate is adjustable using the adjustable mounts.

7. The additive manufacturing system of claim 6, wherein the distance of the recoater blade from the build plate is adjustable by a distance at least as great as a focal range of the laser energy sources.

8. The additive manufacturing system of any of the preceding claims, wherein while the optics assembly directs laser energy from the one or more laser energy sources towards the build plate, the optics assembly is at least partially disposed over the build plate and the recoater is disposed in a recoater park area, and wherein while the recoater forms a layer of precursor material on the build plate, the optics assembly is disposed in an optics assembly park area.

9. The additive manufacturing system of any of the preceding claims, further comprising one or more proximity sensors configured to sense when a relative position of the optics assembly and the recoater within a threshold distance of each other, wherein motion of the optics assembly and recoater are controlled based at least in part on the sensed relative position.

10. The additive manufacturing system of any of the preceding claims, wherein a motion plane of the recoater is substantially parallel to a motion plane of the optics assembly.

11. A method for additive manufacturing comprising: moving an optics assembly parallel to a first axis of a build plate of an additive manufacturing system using a first motion stage; directing laser energy from one or more laser energy sources through the optics assembly and toward the build plate; melting at least a portion of a layer of precursor material disposed on the build plate; moving a recoater parallel to the first axis using the first motion stage; and forming a layer of the precursor material on the build plate.

12. The method of claim 11, wherein moving the optics assembly includes moving the optics assembly linearly along the first linear motion stage, and wherein moving the recoater includes moving the recoater linearly along the first linear motion stage.

13. The method of any one of claims 11-12, wherein moving the optics assembly using the first motion stage and moving the recoater using the first motion stage includes moving the optics assembly and the recoater using a shared magnetic track.

14. The method of any one of claims 11-13, further comprising moving the optics assembly in a direction that is parallel to a second axis of a build plate of the additive manufacturing system, wherein the second axis is perpendicular to the first axis.

15. The method of any one of claims 11-14, wherein the recoater includes a recoater blade, and further comprising adjusting a distance of the recoater blade from the build plate.

16. The method of any one of claims 11-15, wherein the recoater includes a recoater blade, and further comprising adjusting an orientation of the recoater blade relative to the build plate.

17. The method of any one of claims 11-16, further comprising adjusting a position and orientation of an edge of a recoater blade to be within a focal range of the laser energy sources.

18. The method of any one of claims 11-17, further comprising positioning the optics assembly in an optics assembly park area when forming the layer of precursor material on the build plate with the recoater, and positioning the recoater in a recoater park area when laser energy is directed toward a build surface disposed on the build plate by the optics assembly.

19. The method of any one of claims 11-18, further comprising sensing a relative position of the recoater and optics assembly being within a threshold distance, and controlling movement of the recoater and / or optics assembly based at least in part on the sensed relative position.

20. The method of any one of claims 11-19, wherein a motion plane of the recoater is substantially parallel to a motion plane of the optics assembly.

21. The method of any one of claims 11-20, further comprising fusing the precursor material with the laser energy to form one or more parts on the build plate.

22. A part manufactured using the method of any one of claims 11-21.

23. An additive manufacturing system comprising: a primary housing; and a secondary housing coupled to the primary housing, wherein the primary housing and the secondary housing define an interior volume; and a build plate disposed within the interior volume; one or more laser energy sources; an optics assembly disposed within the interior volume, wherein the optics assembly is configured to direct laser energy from the one or more laser energysources toward the build surface to melt at least a portion of a layer of material disposed on the build surface, and wherein the secondary housing is formed of a composite material, and wherein the secondary housing has an optical density of approximately OD-7 or greater.

24. The additive manufacturing system of claim 23, wherein the composite material includes one or more fillers selected from carbon black, lamp black, and iron oxide black.

25. The additive manufacturing system of any one of claims 23-24, wherein the composite material includes one or more fibers selected from fiberglass, carbon fiber, and para- aramid fibers.

26. The additive manufacturing system of any one of claims 23-25, wherein the composite material includes one or more binders selected from epoxy and polyurethane.

27. The additive manufacturing system of any one of claims 23-26, wherein the primary housing comprises a mineral cast frame.

28. The additive manufacturing system of any one of claims 23-27, wherein the secondary housing is formed of a polymer ceramic composite material.

29. The additive manufacturing system of any one of claims 23-28, wherein the secondary housing includes a first inlet and a first outlet, and further comprising a first pump fluidly coupled to the first inlet and the first outlet, and wherein the pump is configured to direct a first flow of gas from the first inlet through the interior volume to the first outlet.

30. The additive manufacturing system of any one of claims 23-29, wherein the first flow of gas directs particulates entrained in the gas within the interior volume to exit the interior volume through the first outlet.

31. The additive manufacturing system of any one of claims 23-30, wherein the primary housing and the secondary housing are configured to form a sealed interior volume.

32. A method for additive manufacturing comprising: directing laser energy from one or more laser energy sources through an optics assembly and toward a build plate of an additive manufacturing system; providing a primary housing and a secondary to form an interior housing, wherein the optics assembly and the build plate are in the interior housing; melting at least a portion of a layer of precursor material disposed on the build plate; wherein the secondary housing is formed of a composite material, and wherein the secondary housing has an optical density of approximately OD-7 or greater.

33. The method of claim 32, wherein the composite material includes one or more fillers chosen from the group of carbon black, lamp black, and iron oxide black.

34. The method of any one of claims 32-33, wherein the composite material includes one or more fibers chosen from the group of fiberglass, carbon fiber, and para-aramid fiber.

35. The method of any one of claims 32-34, wherein the composite material includes one or more binders chosen from the group of epoxy and polyurethane.

36. The method of any one of claims 32-35, wherein the primary housing comprises a mineral cast frame.

37. The method of any one of claims 32-36, wherein the secondary housing is formed of a polymer ceramic composite material.

38. The method of any one of claims 32-37, further comprising directing a first flow of gas from a first inlet of the secondary housing through the interior volume to a first outlet of the secondary housing.

39. The method of any one of claims 32-38, further comprising directing material particles disposed within the interior volume to exit the interior volume through the first outlet using the first flow of gas.

40. The method of any one of claims 32-39, further comprising isolating an interior volume formed by the primary housing and the secondary housing from a surrounding atmosphere.

41. The method of any one of claims 32-40, further comprising fusing the precursor material with the laser energy to form one or more parts on the build surface.

42. A part manufactured using the method of any one of claims 32-41.

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