Abstract: Support structures are used in certain additive fabrication processes to permit fabrication of a greater range of object geometries. For additive fabrication processes with materials that are subsequently sintered into a final part, an interface layer is fabricated between the object and support in order to inhibit bonding between adjacent surfaces of the support structure and the object during sintering. Interface layers suitable for manufacture with an additive manufacturing system may resist the formation of bonds between a support structure and an object during subsequent sintering processes.

Abstract: A materials processing furnace provides for debinding and sintering objects and treating effluent generated by the sintering. A heating chamber maintains a controlled atmosphere for sintering the object. A vacuum pump evacuates an effluent from the heating chamber, and an injector adds a reagent to the evacuated effluent to form a mixed gas. A catalytic converter receives the mixed gas and catalyzes one or more hazardous or offensive compounds of the effluent, thereby converting the effluent to a safer and less offensive exhaust. As a result, the furnace is suitable for operation in an office environment.

Abstract: Support structures are used in certain additive fabrication processes to permit fabrication of a greater range of object geometries. For additive fabrication processes with materials that are subsequently sintered into a final part, an interface layer is formed between the object and support in order to inhibit bonding between adjacent surfaces of the support structure and the object during sintering. The support structure may be a multi-part support structure to mitigate mold lock or facilitate removal from enclosed spaces.

Abstract: Techniques are disclosed for fabricating multi-part assemblies. In particular, by forming release layers between features such as bearings or gear teeth, complex mechanical assemblies can be fabricated in a single additive manufacturing process.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. The shape of an extrusion nozzle may be varied during extrusion to control, e.g., an amount of build material deposited, a shape of extrudate exiting the nozzle, a feature resolution, and the like.

Abstract: Additive fabrication systems generally use support structures to expand the available range of features and geometries in fabricated objects. For example, when a vertical shelf or cantilever extends from an object, a supplemental support structure may be required to provide a surface for fabrication thereon. This process may become more difficult when, e.g., a part will be subjected to downstream processing steps such as debinding or sintering that impose different design rules. To address these challenges and provide a greater range of flexibility and processing speed, it may be useful in certain circumstances to independently fabricate the object and support structures, and then assemble these structures into a composite item for debinding and sintering. This approach also advantageously facilitates various techniques for spraying, dipping, or otherwise applying a release layer between the support structure and the part so that these separate items do not become fused together during sintering.

Abstract: Techniques and compositions are disclosed for composite feedstocks with powder/binder systems suitable for three-dimensional printing, such as fused filament fabrication. The composite feedstocks may include a jacket about a core, with at least the core including a powder material suspended in a binder system and the jacket having a hardness or toughness greater than a hardness or toughness of the core for the feedstock. In general, the harder jacket may protect the core from unintended deformation or damage during transportation, storage, or use. For example, the difference in hardness or toughness between the jacket and the core may facilitate gripping the feedstock (e.g., by gear drives or the like) with a higher amount of force than is otherwise applicable if the feedstock were composed of the core alone, without damaging the core, during a fused filament fabrication process or another additive manufacturing process.

Abstract: A system for de-powdering one or more objects within a powder print bed comprises a build box configured to contain the powder print bed, and a de-powdering subsystem configured to engage the build box. The de-powdering subsystem comprises a vacuum device configured to withdraw loose powder agitated by the air jet device, and a robotic arm configured to convey the vacuum device to one or more locations on the powder print bed. The system may further comprise an air jet device disposed on the robotic arm, the air jet device configured to agitate, with a jet of air, unbound powder within the powder print bed. The system may further comprise a mechanical agitation instrument configured to facilitate agitation of the unbound powder within the powder print bed.

Abstract: A variety of additive manufacturing techniques can be adapted to fabricate a substantially net shape object from a computerized model using materials that can be debound and sintered into a fully dense metallic part or the like. However, during sintering, the net shape will shrink as binder escapes and the base material fuses into a dense final part. If the foundation beneath the object does not shrink in a corresponding fashion, the resulting stresses throughout the object can lead to fracturing, warping, or other physical damage to the object resulting in a failed fabrication. To address this issue, a variety of techniques are disclosed for substrates and build plates that contract in a manner complementary to the object during debinding and sintering.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. A former extending from a nozzle of the printer supplements a layer fusion process by applying a normal force on new material as it is deposited to form the object. The former may use a variety of techniques such as heat and rolling to improve physical bonding between layers.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. The shape of an extrusion nozzle may be varied during extrusion to control, e.g., an amount of build material deposited, a shape of extrudate exiting the nozzle, a feature resolution, and the like.

Abstract: A support structure is fabricated below a printed object to form a structure that prevents or minimizes a drag on a floor while the object shrinks during sintering.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. The shape of an extrusion nozzle may be varied during extrusion to control, e.g., an amount of build material deposited, a shape of extrudate exiting the nozzle, a feature resolution, and the like.

Abstract: The devices, systems, and methods of the present disclosure are directed to dispensing powder for rapid and accurate layer-by-layer fabrication of three-dimensional objects formed through binder jetting. More specifically, a powder may be dispensed from a hopper movable over a volume defined by a powder box to facilitate, for example, rapidly delivering powder in front of a spreader movable across the volume to spread the powder into a layer. The hopper may include a plurality of dispensing rollers along a dispensing region of the hopper. The dispensing rollers may be rotatable relative to one another to control dispensing the powder from the hopper to an area in front of the spreader, reducing wasted motion associated with moving a spreader to retrieve powder from a stationary powder supply and reducing the likelihood of inadvertently delivering powder from the hopper to unintended areas.

Abstract: A support structure is fabricated below a printed object to form a structure that prevents or minimizes a drag on a floor while the object shrinks during sintering.

Abstract: Complexity of a geometry of a desired (i.e., target) three-dimensional (3D) object being produced by an additive manufacturing system, as well as atypical behavior of the processes employed by such a system, pose challenges for producing a final version of the desired 3D object with fidelity relative to the desired object. An example embodiment enables such challenges to be overcome as a function of feedback to enable the final version to be produced with fidelity. The feedback may be at least one value that is associated with at least one characteristic of a printed object following processing of the printed object. Such feedback may be obtained as part of a calibration process of the 3D printing system or as part of an operational process of the 3D printing system.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. A former extending from a nozzle of the printer supplements a layer fusion process by applying a normal force on new material as it is deposited to form the object. The former may use a variety of techniques such as heat and rolling to improve physical bonding between layers.

Abstract: The devices, systems, and methods of the present disclosure are directed to spreading powder to facilitate accurate layer-by-layer fabrication of three-dimensional objects formed through binder jetting. More specifically, a spreader may be moved across a volume defined by a powder box to spread the powder in a layer. As the spreader is moved across the volume, the spreader may vibrate to pack the powder in the volume. By applying this vibration to the powder on a layer-by-layer basis, the resulting three-dimensional object formed through the binder jetting process may have improved density. In turn, such improved density may be useful for forming the three-dimensional objects into finished parts meeting target density standards, which may be particularly useful in the fabrication of metal parts. Further, or instead, applying vibration to the powder may reduce the likelihood of layer-to-layer variations in the three-dimensional object, thus reducing the likelihood of defects in finished parts.

Abstract: A support structure is formed from a support material below a printed object that shrinks similarly to a build material of the printed object during processing in a furnace.

Abstract: The devices, systems, and methods of the present disclosure are directed to thermal energy delivery to facilitate rapid layer-by-layer fabrication of three-dimensional objects formed through binder jetting. More specifically, a powder may be spread to form a layer along a volume defined by a powder box, a binder may be deposited along the layer to form a layer of a three-dimensional object, and the direction of spreading the layer and depositing the binder may be in a first direction and in a second direction, different from the first direction, thus facilitating rapid formation of the three-dimensional object. Thermal energy may be delivered to each layer in the first and second directions to dry or otherwise change the binder and/or the powder to reduce the likelihood of distorting the binder in a given layer as a subsequent layer is rapidly formed over the given layer.