Abstract: According to one aspect, embodiments herein provide a method of reducing distortion in an additively manufactured part comprising forming a shrinking platform from a composite including metal particles embedded in a first matrix, forming shrinking supports from the composite, forming a part from the composite upon the shrinking platform and shrinking supports, forming an interior structure in at least one of the shrinking platform, the shrinking supports, and the part having a plurality of chambers with interconnections therebetween, forming from the shrinking platform, the sintering supports, and the part a portable assembly, and debinding the first matrix in the portable assembly to form a portable assembly in a brown state, wherein debinding the first matrix includes penetrating a fluid debinder into the interior structure of the at least one of the shrinking platform, the shrinking supports, and the part to debind the first matrix from within the interior structure.

Abstract: According to one aspect, embodiments herein provide a furnace for debinding and sintering additively manufactured parts comprising a unitarily formed retort having at least one open side, a heater for heating a sintering volume within the retort to a debinding temperature and to a sintering temperature, an end cap sealing the at least one open side, a forming gas line penetrating the end cap for supplying forming gas at a flowrate, and a heat exchanger within the retort, outside the sintering volume, and adjacent a heated wall of the retort, the heat exchanger having an inlet connected to the forming gas line and an outlet to the sintering volume, wherein the heat exchanger includes a heat exchange tube length sufficient to heat the forming gas to within 20 degrees Celsius of the sintering temperature before the forming gas exits the outlet.

Abstract: A method comprising forming a shrinking platform of layers of a composite, the composite including a metal particulate filler in a first matrix, forming a shrinking support of layers of the composite upon the shrinking platform, forming a first release layer of a release material upon the shrinking support, the release material including a ceramic particulate and a second matrix, and forming a part of the composite upon the shrinking support to form a portable assembly from the combined shrinking platform, shrinking support, release layer and part, wherein substantially horizontal portions of the part are vertically supported by the shrinking platform, wherein the first release layer is configured, after sintering, to separate the part from the shrinking support and to allow the part to be readily removed from the shrinking support, and wherein the shrinking support is configured to prevent the part from distorting during sintering.

Abstract: According to one aspect, embodiments herein provide a method comprising forming a shrinking platform of model material above a build plate, the model material including sinterable metal particles and a first binder, forming a support structure of the model material extending up from the shrinking platform, forming a first portion of the part from successive layers of the model material above the support structure, forming a release layer intervening between a surface of the part and an opposing surface of the support structure or between a surface of the shrinking platform and an opposing surface of the build plate, the release layer including a dispersed ceramic powder and a second binder, and supporting the part, the release layer, and the support structure upon the shrinking platform to form a platform-integrating part assembly, the support structure being configured to prevent the first portion from distorting from gravitational force during sintering.

Abstract: Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an extrusion nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to extruding the filament from the extrusion nozzle.

Abstract: Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an conduit nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to drag the filament from the conduit nozzle.

Abstract: Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an conduit nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to drag the filament from the conduit nozzle.

Abstract: A footwear insole shape is generated by supplying a core reinforced filament having a matrix material impregnating reinforcing strands aligned along the filament, as well as a fill material separately from the core reinforced filament and depositing at least one shell of fill material within an insole shape upon a print bed. The core reinforced filament is deposited to fuse to the fill material within a first reinforcing region formed with respect to the insole shape. A cutter upstream of the nozzle tip cuts the core reinforced filament, and a remainder of the core reinforced filament is deposited to complete the first reinforcing region. A nozzle tip applies pressure to continuously compact the core reinforced filament toward the insole shape as the core reinforced filament is fused to the fill material.

Abstract: In molten metal jetting, where droplets of metal are jetted to 3D print a part, each layer may be traversed each successive layer with a normalizing grinding wheel or other leveling device such as a layer to level each successive layer, and/or the melt reservoir or printing chamber may be filled with an anoxic gas mix to prevent oxidation.

Abstract: According to one aspect, embodiments herein provide a method of reducing distortion in an additively manufactured part comprising forming a shrinking platform from a composite including metal particles embedded in a first matrix, forming shrinking supports from the composite, forming a part from the composite upon the shrinking platform and shrinking supports, forming an interior structure in at least one of the shrinking platform, the shrinking supports, and the part having a plurality of chambers with interconnections therebetween, forming from the shrinking platform, the sintering supports, and the part a portable assembly, and debinding the first matrix in the portable assembly to form a portable assembly in a brown state, wherein debinding the first matrix includes penetrating a fluid debinder into the interior structure of the at least one of the shrinking platform, the shrinking supports, and the part to debind the first matrix from within the interior structure.

Abstract: Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an extrusion nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to extruding the filament from the extrusion nozzle.

Abstract: According to one aspect, embodiments herein provide a method comprising forming a shrinking platform of model material above a build plate, the model material including sinterable metal particles and a first binder, forming a support structure of the model material extending up from the shrinking platform, forming a first portion of the part from successive layers of the model material above the support structure, forming a release layer intervening between a surface of the part and an opposing surface of the support structure or between a surface of the shrinking platform and an opposing surface of the build plate, the release layer including a dispersed ceramic powder and a second binder, and supporting the part, the release layer, and the support structure upon the shrinking platform to form a platform-integrating part assembly, the support structure being configured to prevent the first portion from distorting from gravitational force during sintering.

Abstract: A method comprising forming a shrinking platform of layers of a composite, the composite including a metal particulate filler in a first matrix, forming a shrinking support of layers of the composite upon the shrinking platform, forming a first release layer of a release material upon the shrinking support, the release material including a ceramic particulate and a second matrix, and forming a part of the composite upon the shrinking support to form a portable assembly from the combined shrinking platform, shrinking support, release layer and part, wherein substantially horizontal portions of the part are vertically supported by the shrinking platform, wherein the first release layer is configured, after sintering, to separate the part from the shrinking support and to allow the part to be readily removed from the shrinking support, and wherein the shrinking support is configured to prevent the part from distorting during sintering.

Abstract: A three dimensional printer which prints at using at least one composite material having an inherently abrasive filler or fiber material has a Mohs hardness greater than substantially 1, or a Knoop/Vickers hardness greater than substantially 300 kg/mm2, or a Rockwell C hardness at least C30, and where a nozzle tip may contact a top surface of a previously deposited line of material may have a nozzle body includes a material having a thermal conductivity at least 35 w/M-K to conduct heat to the nozzle, and a nozzle throat and/or nozzle tip each include a material having a Rockwell C hardness at least C40, to resist wear from sliding contact of the nozzle tip with the previously deposited lines of the material being printed or another previously deposited material, or from the material being printed as it is printed through the nozzle throat.

Abstract: Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an conduit nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to drag the filament from the conduit nozzle.

Abstract: A method comprising depositing, in layers, a shrinking platform formed from a composite including metal particles embedded in a first matrix, depositing shrinking supports of the composite upon the shrinking platform, forming a separation clearance dividing at least one shrinking support into fragments, depositing, from the composite, a part upon the shrinking platform and shrinking supports, depositing a separation material intervening between the part and the shrinking supports, the separation material including a ceramic powder and a second matrix, and forming, from the shrinking platform, shrinking supports, separation material, and part, a portable platform assembly in a green state, wherein the shrinking support is configured to prevent the portable platform assembly from distorting from gravitational force during sintering of the metal particles of the assembly in a brown state, and wherein the ceramic powder of the separation material is configured to separate the shrinking support from the part follo

Abstract: A footwear insole shape is generated by supplying a core reinforced filament having a matrix material impregnating reinforcing strands aligned along the filament, as well as a fill material separately from the core reinforced filament and depositing at least one shell of fill material within an insole shape upon a print bed. The core reinforced filament is deposited to fuse to the fill material within a first reinforcing region formed with respect to the insole shape. A cutter upstream of the nozzle tip cuts the core reinforced filament, and a remainder of the core reinforced filament is deposited to complete the first reinforcing region. A nozzle tip applies pressure to continuously compact the core reinforced filament toward the insole shape as the core reinforced filament is fused to the fill material.

Abstract: For 3D printing green parts to be debound and sintered, a binder may be jetted into successive layers of sinterable powder feedstock to build up a 3D shape of a desired 3D green part, associated sintering supports, and an associated shrinking platform. A release material may be deposited to intervene between the 3D green parts and the sintering supports. A placeholder material may be deposited upon bound powder to form 2D layer shapes of placeholder material, and the sinterable powder feedstock refilled and leveled about the placeholder material. Upon debinding, internal cavities corresponding to the 3D shapes of the placeholder material are formed.

Abstract: A method comprising supplying a first material containing a removable binder and greater than 50% volume fraction of a powdered metal having a melting point greater than 1200 degrees C., in which more than 50% of powder particles of the powdered metal have a diameter less than 10 microns, additively depositing the first material in successive layers to form a green body, removing the binder to form a brown body, loading the brown part into a fused tube formed from a second material having an operating temperature less than substantially 1200 degrees C., a thermal expansion coefficient lower than 1×10-6/° C., and a microwave field penetration depth of 10 m or higher, sealing the fused tube and replacing internal air with a sintering atmosphere, applying microwave energy from outside the sealed fused tube to the brown part, and sintering the brown part at a temperature lower than 1200 degrees C.

Abstract: According to one aspect, embodiments herein provide a method for in-process inspection of a 3D printed part with a 3D printer, comprising slicing a three dimensional model to define a plurality of shell volumes, for substantially each shell volume, generating a toolpath for depositing a printing material shell corresponding to the shell volume, transmitting, together with an identification, the toolpaths defining the printing material shells for deposition by a 3D printer, receiving, together with the identification, from the 3D printer a scanned surface profile of a printing material shell, and computing a process inspection including, according to the identification, a comparison between a received scanned surface profile and a toolpath defining a printing material shell.