Abstract: A camera assembly is employed in additive manufacturing to improve the fidelity of a printed object. The camera may scan the surface of a build plate of a 3D printer and an object as it is being printed to generate image data. The image data is processed to detect errors in the build plate or printed object. The printer compensates for the detected errors, which can including modifying the printer configuration and/or modifying the instructions for printing a given object. Using the updated configuration, subsequent objects may then be printed, under a corrected process, to produce an object with fidelity to an original object model.

Abstract: Devices, systems, and methods are directed to the use of nanoparticles for improving strength fabrication of three-dimensional objects formed through layer-by-layer process in which an ink is delivery of a binder delivered onto successive layers of a powder of inorganic particles in a powder bed. More specifically, nanoparticles of inorganic material can may be introduced into one or more layers of the metal powder in the powder bed and thermally processed to facilitate sinter necking, in the powder bed, of the metal particles forming the three-dimensional object. Such sinter necking in the powder bed can may improve strength of the three-dimensional objects being fabricated and, also or instead, can may reduce the likelihood of defects associated with subsequent processing of the three-dimensional objects (e.g., slumping and shrinking in a final sintering stage and/or inadequate densification of the final part).

Abstract: Devices, systems, and methods are directed to coated powder for three dimensional additive manufacturing. The powder may include a first material coated with a second material, with the coating advantageously resisting segregation of the first material and the second material during handling processes associated with fabrication. The reduced segregation of the first material and the second material may facilitate forming finished three-dimensional parts with improved homogeneity of microstructures and, thus, improved physicochemical properties. More generally, the reduced segregation of the first material and the second material achievable through coating the first material with the second material may facilitate binder jet fabrication using a wider array of combinations of first material and second material as compared to binder jet fabrication using mixtures of constituent powders of the first material and the second material.

Abstract: Techniques for debinding additively fabricated parts are described that do not require solvent debinding or catalytic debinding, and that may be performed using only thermal debinding in a furnace. As a result, in at least some cases debinding and sintering may take place sequentially within a single furnace. In some embodiments, the techniques may utilize particular materials as binders that allow for a thermal debinding process that does not negatively affect the parts.

Abstract: A system and corresponding method to move a rod of build material in a three-dimensional (3D) printing system uses a pusher. The rod of build material has distal and proximal ends relative to an extrusion head. The distal and proximal ends having distal and proximal end surfaces, respectively. The pusher engages with the rod and applies an axial force to at least a portion of the distal end surface of the rod for at least a portion of a path the rod travels toward the extrusion head. The axial force actuates the rod of build material without alteration, such as by shaving, fracturing, or otherwise deforming the rod of build material.

Abstract: A system and corresponding method to move a rod of build material in a three-dimensional (3D) printing system uses a pusher. The rod of build material has distal and proximal ends relative to an extrusion head. The distal and proximal ends having distal and proximal end surfaces, respectively. The pusher engages with the rod and applies an axial force to at least a portion of the distal end surface of the rod for at least a portion of a path the rod travels toward the extrusion head. The axial force actuates the rod of build material without alteration, such as by shaving, fracturing, or otherwise deforming the rod of build material.

Abstract: A system and corresponding method to move a rod of build material in a three-dimensional (3D) printing system uses a pusher. The rod of build material has distal and proximal ends relative to an extrusion head. The distal and proximal ends having distal and proximal end surfaces, respectively. The pusher engages with the rod and applies an axial force to at least a portion of the distal end surface of the rod for at least a portion of a path the rod travels toward the extrusion head. The axial force actuates the rod of build material without alteration, such as by shaving, fracturing, or otherwise deforming the rod of build material.

Abstract: Techniques for depowdering additively fabricated parts are described in which powder is separated from parts by creating a large pressure differential between the powder and parts and a nearby location. The pressure differential may cause gas to quickly flow into and/or around the powder and parts, thereby producing a force against the powder and parts. Since the powder is generally much lighter than the parts, this force may be much more effective at moving the powder than moving the parts. As a result, the powder and parts may be separated from one another. The pressure differential may be created in various ways, such as by holding the parts and part in a chamber that is pressurized with air and/or other gas(es). Rapid depressurization of the chamber may produce the aforementioned pressure differential, leading to powder movement away from the parts.

Abstract: A method for binder jetting a three-dimensional (3D) object includes receiving a geometry of the object to be printed and generating instructions for printing the object. Generating the instructions includes slicing the geometry of the object into a series of cross-sectional shapes corresponding to where a binder fluid will be deposited onto a powder bed to form the object, and including a plurality of negatively printed features within at least some of the series of cross-sectional shapes, wherein an amount of binder fluid to be deposited in the negatively printed features is less than an amount of binder fluid to be deposited in a remainder of the cross-sectional shape. The amount of binder fluid to be deposited in the negatively printed features and a size of the negatively printed features is configured to allow gas to escape from the powder bed.

Abstract: Systems, methods, components, and materials are disclosed for stereolithographic fabrication of three-dimensional, dense objects. A resin including at least one component of a binder system and dispersed particles can be exposed to an activation light source. The activation light source can cure the at least one component of the binder system to form a green object, which can include the at least one component of the binder system and the particles. A dense object can be formed from the green object by removing the at least one component of the binder system in an extraction process and thermally processing particles to coalesce into the dense object.

Abstract: Techniques for depowdering additively fabricated parts are described. The techniques utilize various mechanisms to separate powder from parts. For instance, techniques for depowdering described herein may include fabrication of auxiliary structures in addition to fabrication of parts. Certain auxiliary structures may aid with depowdering operations, and may be fabricated along with parts during an additive fabrication process. The auxiliary structures may be shaped and/or have positional and/or geometrical relationships to the parts during fabrication. For instance, an auxiliary structure may include a cage structure fabricated around one or more parts.

Abstract: Disclosed is a method and material system for fabricating metal infiltrated objects having a high volume fraction of infiltrant relative to the infiltrated preform. In an embodiment method, a composite is formed into the shape of a desired object, the composite including a skeletal phase and a fugitive phase. The fugitive phase is then removed to create a self-supporting porous skeletal structure. The porous skeletal structure is then infiltrated with the infiltrant to achieve a densified object.

Abstract: Methods provide for fabricating objects through additive manufacturing in a manner that compensates for deformations introduced during post-print processing, such as sintering. An initial model may be divided into a plurality of segments, the initial model defining geometry of an object. For each of the segments, modified geometry may be calculated, where the modified geometry compensates for a predicted deformation. Print parameters can then be updated to incorporate the modified geometry, where the print parameters define geometry of the printed object (e.g., configuration settings of the printer, a tool path, an object model). The object may then be printed based on the updated print parameters.

Abstract: The present invention is directed to systems and methods for automatically generating mechanical part designs and manufacturing specifications/instructions that account for geometric distortions that may occur during manufacturing or post-processing.

Abstract: An additive manufacturing method includes depositing a first amount of metal powder onto a powder bed of a printing system, spreading the first amount of metal powder across the powder bed to form a first layer, and depositing a first amount of binder material on the first layer. The additive manufacturing method also includes exposing the first layer to a first lighting condition, imaging the first layer under the first lighting condition to generate a first image, analyzing the first image of the first layer, and determining whether to adjust at least one printing parameter based on the analyzing.

Abstract: Methods of additive manufacturing using noble metals and/or copper metal, and binder compositions for use during the additive manufacturing methods, are generally described. In some instances, the methods of additive manufacturing include de-binding (and in some cases sintering steps) that afford metal-based composites, de-bound metal structures, and metal objects containing noble metals (e.g., silver, gold, platinum) and/or copper that have improved properties, such as relatively high densities. In certain aspects, combinations of certain metal powders (e.g., noble metal and/or copper powders) with certain binder compositions may result in improved properties of resulting metal objects produced by the additive manufacturing process, such as relatively low surface roughnesses. The binder compositions described may include a low molecular weight polymer (e.g., including an acrylic acid repeat unit) and, in some cases, a cross-linking agent.

Abstract: A system and corresponding method for additive manufacturing of a three-dimensional (3D) object to improve packing density of a powder bed used in the manufacturing process. The system and corresponding method enable higher density packing of the powder. Such higher density packing leads to better mechanical interlocking of particles, leading to lower sintering temperatures and reduced deformation of the 3D object during sintering. An embodiment of the system comprises means for adjusting a volume of a powder metered onto a top surface of the powder bed to produce an adjusted metered volume and means for spreading the adjusted metered volume to produce a smooth volume for forming a smooth layer of the powder with controlled packing density across the top surface of the powder bed. The controlled packing density enables uniform shrinkage, without warping, of the 3D object during sintering to produce higher quality 3D printed objects.

Abstract: Devices, systems, and methods are directed to the use of vapor phase change in binder jetting processes for forming three-dimensional objects. In general, a vapor of a first fluid may be directed to a layer of a powder spread across a build volume. The vapor may condense to reduce mobility of the particles of the powder of the layer. For example, the condensing vapor may reduce the likelihood of particle ejection from the layer and, thus, may reduce the likelihood of clogging or otherwise degrading a printhead used to jet a second fluid (e.g., a binder) to the layer. Further, or instead, the condensing vapor may increase the density of the powder in the layer which, when repeated over a plurality of layers forming a three-dimensional object, may reduce the likelihood of slumping of the part during sintering.