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.

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 one or more non-wetting surfaces in the vicinity of a discharge orifice of the nozzle. Such non-wetting surfaces can reduce the likelihood that wetting of the liquid metal in the vicinity of a discharge orifice of a nozzle will interfere with ejection of liquid metal droplets from the discharge orifice and, thus, can facilitate delivering droplets with accuracy suitable for commercially viable manufacturing using liquid metal to fabricate objects.

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. An electric current delivered to produce the magnetohydrodynamic forces can be controlled between a pulsed electric current and a direct electric current to change the rate of liquid metal ejection from a nozzle. For example, the electric current can be switched between a pulsed electric current and a direct electric current based at least in part on a position of the nozzle along the controlled pattern, providing accuracy of liquid metal deposition along portions of the pattern having more detail and providing speed of liquid metal deposition along portions of the pattern having less detail.

Abstract: Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal from a nozzle along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. Electrodes used to deliver electric current across a firing chamber of the nozzle are formed of the same material as the liquid metal being ejected from the nozzle. For example, respective interfaces between the electrodes and the liquid metal can be molten material. Forming the electrodes and the liquid metal of the same material can facilitate, for example, ejecting liquid metals having high melt temperatures.

Abstract: Devices, systems, and methods are directed to the pneumatic ejection of liquid metal from a nozzle moving along a controlled three-dimensional pattern to fabricate a three-dimensional object through additive manufacturing. The metal is movable into the nozzle as a valve is actuated to control movement of pressurized gas into the nozzle. Such movement of metal into the valve as pressurized gas is being moved into the nozzle to create an ejection force on liquid metal in the nozzle can reduce or eliminate the need to replenish a supply of the metal in the nozzle and, therefore can facilitate continuous or substantially continuous liquid metal ejection for the fabrication of parts.

Abstract: Devices, systems, and methods are directed to applying magnetohydrodynamic forces to liquid metal to eject liquid metal from a nozzle along a controlled pattern, such as a controlled three-dimensional pattern as part of additive manufacturing of an object. A feeder system can provide a continuous or substantially continuous supply of a solid metal to the nozzle to facilitate a correspondingly continuous or substantially continuous process for ejecting liquid metal as part of a commercially viable manufacturing process.

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. Magnets used to form the magnetohydrodynamic forces are thermally managed to facilitate directing strong magnetic fields into liquid metals at high temperatures. Such strong magnetic fields can be useful for imparting, under otherwise equivalent conditions, higher magnetohydrodynamic forces to liquid metal being ejected from a nozzle to form an object.

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.

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.

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.

Abstract: Fused filament fabrication using metal based multi-phase (MBMP) build materials, creates a build with object portions and support portions adhered to each other that must be separated. Different object portions are more delicate or problematic than others. Methods for tuning or specifying the strength of adhesion at interfaces between such object and support portions include providing a release skin of powder or other material at such interfaces. Strength of adhesion also varies based on the liquid fraction of material deposited to form interfaces, generally with relatively higher liquid fraction leading to stronger adhesion. Liquid fraction is governed by MBMP material composition and temperature at deposition. Strength can be tuned by printing interfaces of the same material at different temperatures, or different materials at the same or different temperatures. Support portions may be entirely of weaker adhesion. Joining portions may separate with object or support.

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 nozzle for extruding metal containing multi phase (MCMP) build material is heated by an induction coil. The nozzle effective radius is larger than an induction skin depth in the nozzle, which is larger than 1/15 the radius, and less than the nozzle length. The nozzle material performance index, based on resistivity and magnetic permeability, is higher than that of the build material, and components of a build platform, particularly a removable sheet. The coil radius is less than 1.4 times the nozzle effective radius. The nozzle may be of several annular sections, of which that of the bore may be removable and wear resistant. The nozzle may be of multiple graphite grades, including copper infused. The coil axial extent may be less than the nozzle length, and it may be located nearer to the outlet. An adhesion control layer on a build sheet may enhance or reduce adhesion thereto.

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.