Desktop Metal, Inc.

Methods and systems for forming break-away supports during additive manufacturing of objects via magnetohydrodynamic (MHD) jetting. In MHD jetting supports may be required for certain overhang areas and/or other features. On a surface or surfaces that will contact the object and/or a build plate (or the like), a plasma discharge may be conducted to create a treated surface. The treated surface bonds weakly with the support relative to inter-layer bonds between construction layers. Thus, after printing is complete the supports can be easily separated without strong mechanical forces that may have otherwise damaged the printed object.

Embodiments relate to methods for course correction of a robotic arm in 3D printing applications involves applying arbitrary offsets along X-, Y-, Z-, and theta Z-axes, enabling correction of arbitrary repeatable errors in the arm's nominal (uncorrected) trajectory. By applying those offsets in the reverse, their effects can be cancelled or reduced to achieve repeatable near-planarity in the path of travel.

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. Electric current delivered to a meniscus of the liquid metal in a quiescent state can be directed to exert a pullback force on the liquid metal. The pullback force can be sufficient to draw the liquid metal, in the quiescent state, in a direction toward the nozzle to reduce the likelihood of unintended wetting of surfaces of the nozzle between uses of the nozzle.

The present invention relates to powder-layer three-dimensional printers ( 2 ) having a discrete supply hopper ( 340 ) and a recoater ( 20 ). The discrete supply hopper ( 340 ) is configured to transfer a build powder to the recoater ( 20 ) in a manner that enhances the uniformity of build powder layers that are dispensed from the recoater ( 20 ). In some embodiments, at least one of the discrete supply hopper and the powder hopper of the recoater is adapted to selectively contact the other, seal against the other, and/or have one partially inserted inside the other so as to diminish or prevent powder pluming during the transfer of build powder from the discrete supply hopper to the recoater.

The present disclosure includes a furnace for heating and/or sintering one or more three-dimensional printed metal parts. The furnace includes a furnace chamber, insulation within the furnace chamber, a retort within the furnace chamber, and one or more getters containing getter material. The retort is configured to receive the one or more three-dimensional printed metal parts.

A furnace may include an outer wall defining a chamber, the chamber including an internal cavity configured to receive one or more parts, at least one heater positioned within the chamber, the at least one heater being configured to generate temperatures of at least about 800 degrees Celsius within the internal cavity, and a vacuum pump configured to apply a vacuum to at least a portion of the chamber. The furnace may also include at least one layer of inner insulation and at least one layer of outer insulation disposed outward of the inner insulation with respect to the chamber, the at least one layer of outer insulation being sealed with respect to the at least one layer of inner insulation.

Techniques are described for fabricating sinterable metallic parts by coating a metal powder with a first material, and by depositing a binder composition onto the metal powder that contains a second material, then causing the first and second materials to react to form a polymer. The first and second materials may be selected so that they combine to produce a desired polymer. The binder composition may be deposited using conventional binder jetting techniques.

A powder collection system for use in binder jetting additive manufacturing. A downdraft system includes at least one powder collection chute disposed in an interior of a binder jetting printer and adjacent to a print deck. The downdraft system is configured to receive an amount of excess build material powder dislodged from the print deck by a powder spreading process. A pneumatic conveyance system including at least one conveyance plumbing tube provides gaseous communication between the downdraft system and a powder collection unit. A gas management system provides a flow of process gas through the downdraft system and the pneumatic conveyance system at a rate sufficient to convey the excess build material powder received by the downdraft through the pneumatical conveyance system to the powder collection unit. The powder collection unit separates the excess build material powder from the flow of process gas and collects it.

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.

A method for improving part quality in additive manufacturing involving jetting liquid metal. Limiting the amounts of magnesium and zinc in a meniscus material to below predetermined thresholds improves jetting quality. Further, ensuring an amount of Strontium is above a predetermined threshold further improves jetting of the liquid metal.