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: A method is provided for printing a three-dimensional object. The method comprises, depositing a layer of metal powder onto a powder bed of a three-dimensional printer. A liquid is heated to generate a vapor. The liquid is removed from the vapor to dry the vapor by heating the vapor above a condensation temperature of the liquid. The dry vapor is deposited onto the powder bed of the three-dimensional printer.

Abstract: A furnace system for printing an object using additive manufacturing. The furnace system may include a furnace chamber; an outlet fluidly coupled to the furnace chamber for removal of an exhaust gas from the furnace chamber; a conduit fluidly coupled to the outlet; an oxygen injector fluidly coupled to the conduit; an isolation system fluidly coupled to the conduit between the furnace chamber and the oxygen injector; and a catalyst enclosure comprising an oxidizing catalyst.

Abstract: A method of printing an object using additive manufacturing includes depositing an amount of powder onto a print bed, spreading the amount of powder into a layer, depositing, in a first direction, a fluid configured to bind the powder onto at least a portion of the layer in a cross-sectional shape of the object to form the object, and depositing the fluid configured to bind the powder onto at least a portion of the layer adjacent to a leading edge of the cross-sectional shape of the object in the first direction to form at least one buffer element upstream of the cross-sectional shape of the object in the first direction.

Abstract: According to some aspects, techniques are provided for fabricating sinterable metallic parts through the application of directed energy to a build material. In particular, applying energy to a build material comprising a polymer mixed with a metal powder may cause the polymer to form a cohesive structure with the metal powder. As a result, the polymer acts as a “glue” to produce a metallic green part without local melting of the metal. The green part may subsequently be sintered to remove the polymer and produce a fully dense metal part. Optionally, a step of debinding may also be performed prior to, or simultaneously with, sintering.

Abstract: A build box associated with a powder bed fabrication system may comprise a housing defining a housing cavity, and a powder print bed disposed within the housing cavity. The powder print bed may be characterized by state information. The build box may further comprise a medium configured to facilitate access to the state information, and a coupling interface for removably engaging the build box with at least one subsystem of the powder bed fabrication system. The state information may comprise one or more state information elements of object identification, object location, current processing state, next subsystem processing step, previous subsystem processing step, object model information, object material composition, and current powder print bed temperature profile. The medium may comprise a memory device coupled with a transceiver. The medium may alternatively comprise an RFID device, or an optically perceivable designator, such as a bar code or QR code.

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: 3D-printed parts may include binding agents to be removed following an additive manufacturing process. A debinding process removes the binding agents by immersing the part in a solvent bath causing chemical dissolution of the binding agents. The time of exposure of the 3D-printed part to the solvent is determined based on the geometry of the part, wherein the geometry is applied to predict the diffusion of the solvent through the 3D-printed part. The 3D-printed part is then immersed in the solvent bath to remove the binding agent, and is removed from the solvent bath after the time of exposure.

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 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. Porosity of one or more predetermined portions of objects fabricated from an accumulation of liquid metal droplets ejected using magnetohydrodynamic force can be controlled to form interfaces between support structures and parts within the object. Higher porosity along the interfaces, as compared to porosity along the support structures and the parts, can be useful for facilitating separation of the parts from the support structures.

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: A 3D printer includes a build plate providing a surface on which an object is printed. Prior to printing, a sheet is fixed to the surface of the build plate. The sheet is composed of a material that adheres to a binder component of the feedstock used to print the object. During printing, the first layer of the printed object forms a bond with the sheet, which secures the location of the first layer and resists movement of the object during printing. Following printing and the object gaining sufficient rigidity, the object and sheet can be removed together from the printer. The sheet may then be peeled from the object, and the object can undergo debinding and/or sintering to create a finished object.

Abstract: Assemblies fabricated by additive manufacturing include an object and a base plate providing support to the object during the manufacturing process. The geometry of the base plate is defined to optimize space and material constraints. During sintering, the base plate is reduced in area in a manner complementing the reduction in the footprint of the object, preserving the fidelity of the finished object.

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: 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 furnace system includes a heating chamber, a retort assembly, and a waveguide. The heating chamber includes a shell encompassing an insulation layer and a working volume, where the working volume is configured to receive at least one part for heat treatment. The retort assembly is supported within the insulation layer and includes an inner retort surface facing the working volume. The inner retort surface is formed of at least one carbon compound reflective of microwave radiation, and the retort assembly defines a retort aperture. The waveguide is configured to direct microwave radiation from a microwave source to the retort aperture.

Abstract: A debinder provides for debinding printed green parts in an additive manufacturing system. The debinder can include a storage chamber, a process chamber, a distill chamber, a waste chamber, and a condenser. The storage chamber stores a liquid solvent for debinding the green part. The process chamber debinds the green part using a volume of the liquid solvent transferred from the storage chamber. The distill chamber collects a solution drained from the process chamber and produces a solvent vapor from the solution. The condenser condenses the solvent vapor to the liquid solvent and transfer the liquid solvent to the storage chamber. The waste chamber collects a waste component of the solution.