Abstract: A control loop for extrusion of a metallic build material such as bulk metallic glass measures a force required to extrude the build material, and uses this sensed parameter to estimate a temperature of the build material. The temperature, or a difference between the estimated temperature and a target temperature, can be used to speed or slow extrusion of the build material to control heat transfer from a heating system along the feedpath. This general control loop may be modified to account for other possible conditions such as nozzle clogging or the onset of crystallization.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. The Seebeck effect can be employed to monitor a temperature difference between a build material and a nozzle that is extruding the build material based on voltage. The temperature difference can, in turn, be used to control operation of the printer or to determine an absolute temperature based on direct measurement of a temperature of the nozzle.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. A nozzle cleaning fixture may be provided for the printer that is shaped to physically dislodge solidified build material and other contaminants from the nozzle. A robotic system for the printer can be used to maneuver the nozzle into engagement with the nozzle cleaning fixture for periodic cleaning, or in response to a diagnostic condition or the like indicating a clogged nozzle.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. A plasma depassivation wash is applied during deposition to remove oxidation and improve interlayer bonding between successive layers of the metallic build material. Other techniques such as ultrasonic vibration, formation of energy directors, joule heating, and the like, may be used in combination to form a mechanically robust bond between layers.

Abstract: A printer fabricates an object from a build material based on a computerized model and a fused filament fabrication process. A nozzle for depositing the build material has an interior diameter approaching an outer diameter of build material fed to the nozzle in order to reduce extrusion and resistance forces imposed by the nozzle during deposition, while adequately constraining a planar position of the build material for accurate material deposition in a computer-controlled fabrication process.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a metallic build material. One or more contact probes may be used to detect a height and/or position of a nozzle, e.g., to zero, center, or otherwise calibrate the nozzle prior to a print, or to determine a height relative to a deposited layer of build material during fabrication.

Abstract: A printer fabricates an object from a computerized model using a fused filament fabrication process and a build material. One or more energy directors such as ridges are formed in an exposed surface of the deposited build material to provide regions of high, localized contact force that can improve interlayer bonding between successive layers of the build material. An ultrasonic vibrator can also usefully be incorporated into the printer to apply additional energy along these energy directors during deposition of a subsequent layer.

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. 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: 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. 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 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: 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: 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.