Abstract: 3D printing using metal containing multi phase materials is prone to nozzle clogging and flow artifacts. These can be mitigated by monitoring process conditions and taking action at times based on other conditions. Forces, physical regularity, and temperatures can be monitored and service can be taken based on these, immediately, or at dynamic future points, short or longer term, such as completion of a segment or layer, or before critical geometry. Process conditions can be logged and service time can be based on functions of individual and combinations of logged data. Operating windows can be adjusted based on same. Service includes dwell time at high and low temperatures, treatment material provided into the nozzle to change the liquid composition therein. Plungers and fluid jets can expel material from nozzle inlet or outlet. Dwelling at various temperatures can liquefy clogs or cause rupture by disparate volume changes of cooling materials.

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: Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. The magnetohydrodynamic force can be pulsed to eject droplets of the liquid metal to provide control over accuracy of the object being fabricated. The pulsations can be applied in fluid chambers having high resonance frequencies such that droplet ejection can be effectively controlled over a wide range of frequencies, including high frequencies suitable for liquid metal ejection at rates suitable for commercially viable three-dimensional fabrication.

Abstract: Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Nozzles associated with these devices, systems, and methods include a combination of materials suitable for withstanding prolonged exposure to high temperatures associated with certain liquid metals while facilitating efficient delivery of current to produce magnetohydrodynamic forces controllable over a range of frequencies associated with commercially viable three-dimensional fabrication.

Abstract: For conditioning build material for fused filament fabrication, thermal power is both added to and removed from a nozzle in a manner that can reduce sensitivity of the nozzle temperature to fluctuations in build material feed rate. The amount of thermal power added is at least as large as the sum of the amount removed, the amount to condition the material, and losses to the environment. The amount removed may be at least as large as half the thermal power required to condition the material to extrusion temperature, and may be comparable to, or much larger than the conditioning amount. The larger the ratio of the amount removed to the conditioning amount, the less sensitive the nozzle temperature will be to fluctuations in build material feed rate. Fine temperature control arises, enabling building with metal-containing multi-phase materials or other materials that have a narrow working temperature range.

Abstract: 3D printing using certain materials, such as metal containing multi-phase materials can be prone to clogs and other flow interruptions. Providing build material according to feed rate profiles having varying rates can mitigate these problems. Each feed rate profile can be broken up into blocks of time, some of which relate to fabricating the exterior geometry of the object. Each block of time can be represented by a FFT. The blocks that relate to the exterior are represented by a FFT that has significant high frequency content of 1 Hz or greater. It is beneficial to use profiles including feed rates outside of a range of feed rates suitable for steady state extrusion, being either higher or lower rates than the range limits. A combination of feed rate profiles based only on clog and flow interruption mitigation and operational to print the part according to a model can be used.

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: 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. 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: 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: 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: 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.

Abstract: Devices, systems, and methods are directed to the use of nanoparticles for improving fabrication of three-dimensional objects formed through layer-by-layer delivery of an ink onto a powder of metal particles in a powder bed. More specifically, the ink may include high aspect ratio nanoparticles, such as filaments. As compared to nanoparticles having lower aspect ratios, high aspect ratio nanoparticles may facilitate bridging more surface of the metal particles in the powder bed. As the three-dimensional objects including the high aspect ratio nanoparticles and the metal particles are thermally processed, the increased bridging associated with the high aspect ratio nanoparticles may result in increased bonded area between the nanoparticles and the metal particles and, thus, three-dimensional objects that are more robust with respect to subsequent processing required to form the three-dimensional objects into finished parts.

Abstract: Devices, systems, and methods are directed to the use of nanoparticles for improving fabrication of three-dimensional objects formed through layer-by-layer delivery of an ink onto a powder of metal particles in a powder bed. More specifically, the ink may include ceramic nanoparticles that may be maintained in a stable form, providing a shelf-life suitable for transportation and storage of the ink in large-scale commercial operations. The ink may be delivered onto the powder of the metal particles in the powder bed, where the ceramic nanoparticles may interact with the metal particles to improve strength of the three-dimensional objects being fabricated. Also, or instead, the nanoparticles may reduce the likelihood of defects associated with subsequent processing of the three-dimensional objects (e.g., slumping and shrinking and/or inadequate densification of the final part).

Abstract: A powder bed is filled layer by layer with a sinterable powder and a liquid binder. After the liquid binder is applied, the liquid binder can be activated, e.g., by selectively curing cross-sections of the binder according to a computerized three-dimensional model of an object. In this manner, a sinterable net shape object can be formed within the powder bed layer by layer. The sinterable net shape can then be removed, debound as appropriate, and sintered into a final part.

Abstract: Binder jetting techniques can be used to deposit and bind metallic particles or the like in a net shape for debinding and sintering into a final part. Where support structures are required to mitigate deformation of the object during the debinding and/or sintering, an interface layer may be formed between the support structures and portions of the object in order to avoid bonding of the support structure to the object during sintering.

Abstract: A powder bed is filled layer by layer with a powdered build material containing an activatable binder. The binder in each new layer is locally activated according to a computerized three-dimensional model of an object to fabricate, layer by layer, a sinterable net shape of the object within the powder bed. The sinterable net shape can then be removed, debound as appropriate, and sintered into a final part.

Abstract: Binder jetting techniques can be used to deposit and bind metallic particles or the like in a net shape for debinding and sintering into a final part. Where support structures are required to mitigate deformation of the object during the debinding and/or sintering, an interface layer may be formed between the support structures and portions of the object in order to avoid bonding of the support structure to the object during sintering.