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 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: 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: Mold lock is remediated by performing a layer-by-layer, two-dimensional analysis to identify unconstrained removal paths for any support structure or material within each two-dimensional layer, and then ensuring that aligned draw paths are present for all adjacent layers, all as more specifically described herein. Where locking conditions are identified, a sequence of modification rules are then applied, such as by breaking support structures into multiple, independently removable pieces. By addressing mold lock as a series of interrelated two-dimensional geometric problems, and reserving three-dimensional remediation strategies for more challenging, complex mold lock conditions, substantial advantages can accrue in terms of computational speed and efficiency.

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: 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 that this feature can be fabricated upon. This process may become more difficult when a surface requiring support is enclosed within a cavity inside an object being fabricated. Techniques are disclosed herein for fabricating supports that can be removed from within cavities in an object.

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: A printer fabricates an object from a computerized model using a fused filament fabrication process and a bulk metallic glass build material. By heating the bulk metallic glass at an elevated temperature in between an object and adjacent support structures, an interface layer can be interposed between the object and support where the bulk metallic glass becomes crystallized to create a more brittle interface that facilitates removal of the support structure from the object after fabrication.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material such as a bulk metallic glass. A thermal history of the object may be maintained, e.g., on a voxel-by-voxel basis in order to maintain a thermal budget throughout the object suitable for preserving the amorphous, uncrystallized state of the bulk metallic glass, and to provide a record for prospective use and analysis of the object.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a bulk metallic glass build material. By using thermally mismatched bulk metallic glasses for an object and adjacent support structures, the interface layer between these structures can be melted and crystallized to create a more brittle interface that facilitates removal of the support structure from the object after fabrication.

Abstract: In an aspect, a printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. An ultrasonic vibrator is incorporated into the printer to improve the printing process, e.g., by disrupting a passivation layer on the deposited material to improve interlayer bonding, and to prevent adhesion of the metallic build material to a nozzle and other printer components.

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 printer fabricates an object from a computerized model using a fused filament fabrication process and a bulk metallic glass. A shearing engine within a feed path for the bulk metallic glass actively induces a shearing displacement of the bulk metallic glass to mitigate crystallization, more specifically to extend processing time for handling the bulk metallic glass at elevated temperatures.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process. The exit of the nozzle may include a number of concentric rings, where each of which may be selectively opened or closed during extrusion to control extrusion properties such as a volume of extrudate or a mixture of material exiting the nozzle.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. Joule heating is applied to an interface between adjacent layers of the object by creating an electrical circuit across the interface and applying pulsed current sufficient to join the metallic build material across the adjacent layers.

Abstract: Thermal parameters for an additive manufacturing process are estimated using computer modeling, and these thermal parameters are used to control the additive manufacturing process. For example, the thermal parameters may be estimated based on bulk material properties, object geometry, control signals to thermal components of a system, and so forth.

Abstract: An additive manufacturing system uses electrohydrodynamic (EHD) printing techniques to form a metallic object based upon a digital model. A metal build material is melted within a reservoir and expelled through an outlet of an expeller in a controlled manner using EHD force to modulate surface tension on a meniscus of the liquid metal at the outlet of the expeller. Concurrently, a positioning robotics system moves the expeller relative to a print bed along a toolpath that forms the solidifying metal droplets into a net shape according to the digital model.

Abstract: A metallic electrohydrodynamic (EHD) three-dimensional printer fabricates an object while surface characteristics of the object are monitored. Sensors acquire data on surface characteristics, and feedback related to these surface characteristics is used to adjust the fabrication process, e.g., where the surface characteristics deviate from a target surface shape.

Abstract: Processing data in a computer-aided design (CAD) system includes determining that a feature of a three-dimensional model has a condition that requires correction. The condition is automatically corrected by performing an action. The action may be an action that reorders a sequence of features in the three-dimensional model, an action that changes at least one parameter of the feature, an action that deletes a feature reference, or an action that changes a feature reference. Furthermore, the action may have one or more constraints that bound the action to a set of features that are directly and indirectly related to the feature on which the action operates.