An additive manufacturing (AM) system includes a housing defining a chamber and a build platform disposed in a lower portion of the chamber. The AM system includes an upper gas inlet disposed in a side-wall and in an upper portion of the chamber and configured to supply an upper gas flow parallel to the build platform. The AM system includes a lower gas inlet in the lower portion of the chamber, wherein the lower gas inlet includes one or more pairs of dividing walls extending from the side-wall toward the build platform and configured to guide the lower gas flow at one or more flow angles with respect to the build platform. The AM system includes at least one gas delivery mechanisms to regulate flow characteristics of the upper and lower gas flows, and includes a gas outlet to discharge the upper and lower gas flows from the chamber.

An additive manufacturing (AM) system includes a housing defining a chamber and a build platform disposed in a lower portion of the chamber. The AM system includes an upper gas inlet disposed in a side-wall and in an upper portion of the chamber and configured to supply an upper gas flow parallel to the build platform. The AM system includes a lower gas inlet in the lower portion of the chamber, wherein the lower gas inlet includes one or more pairs of dividing walls extending from the side-wall toward the build platform and configured to guide the lower gas flow at one or more flow angles with respect to the build platform. The AM system includes at least one gas delivery mechanisms to regulate flow characteristics of the upper and lower gas flows, and includes a gas outlet to discharge the upper and lower gas flows from the chamber.

Described herein are compositions, methods, and systems for printing metal three-dimensional objects. In an example, described is a method of printing a three-dimensional object comprising: (i) depositing a metal powder build material, wherein the metal powder build material has an average particle size of from about 10 μm to about 250 μm; (ii) selectively applying a binder fluid on at least a portion of the metal powder build material, wherein the binder fluid comprises an aqueous liquid vehicle and latex polymer particles dispersed in the aqueous liquid vehicle; (iii) heating the selectively applied binder fluid on the metal powder build material to a temperature of from about 40° C. to about 180° C.; and (iv) repeating (i), (ii), and (iii) at least one time to form the three-dimensional object.

Described herein are compositions, methods, and systems for printing metal three-dimensional objects. In an example, described is a method of printing a three-dimensional object comprising: (i) depositing a metal powder build material, wherein the metal powder build material has an average particle size of from about 10 μm to about 250 μm; (ii) selectively applying a binder fluid on at least a portion of the metal powder build material, wherein the binder fluid comprises an aqueous liquid vehicle and latex polymer particles dispersed in the aqueous liquid vehicle; (iii) heating the selectively applied binder fluid on the metal powder build material to a temperature of from about 40° C. to about 180° C.; and (iv) repeating (i), (ii), and (iii) at least one time to form the three-dimensional object.

Apparatuses for dynamically sensing infrared (IR) radiation in an electron beam powder bed fusion (EB-PBF) printer are provided. A radiation collector receives radiation from a surface of the powder bed. An IR-transparent material rejects one or more non-IR wavelengths, and a lens focuses the IR radiation onto an optical fiber. The IR radiation is carried from the vacuum chamber of the printer to a sensor, where IR information is determined based on the received IR radiation. The IR information may be received from the sensor and used by the print controller to modify one or more parameters, such as beam intensity or scanning rate, on the fly or during the next print cycle. An occlusion member can be used to selectively block or expose the radiation collector to protect the radiation collector from condensation of vapor from vaporization of particles at high temperatures.

Apparatuses for dynamically sensing infrared (IR) radiation in an electron beam powder bed fusion (EB-PBF) printer are provided. A radiation collector receives radiation from a surface of the powder bed. An IR-transparent material rejects one or more non-IR wavelengths, and a lens focuses the IR radiation onto an optical fiber. The IR radiation is carried from the vacuum chamber of the printer to a sensor, where IR information is determined based on the received IR radiation. The IR information may be received from the sensor and used by the print controller to modify one or more parameters, such as beam intensity or scanning rate, on the fly or during the next print cycle. An occlusion member can be used to selectively block or expose the radiation collector to protect the radiation collector from condensation of vapor from vaporization of particles at high temperatures.

The present disclosure provides three-dimensional (3D) printing processes, apparatuses, software, and systems for the production of at least one desired 3D object. The 3D printer system (e.g., comprising a processing chamber, build module, or an unpacking station) described herein may retain a desired (e.g., inert) atmosphere around the material bed and/or 3D object at multiple 3D printing stages. The 3D printer described herein comprises one or more build modules that may have a controller separate from the controller of the processing chamber. The 3D printer described herein comprises a platform that may be automatically constructed. The invention(s) described herein may allow the 3D printing process to occur for a long time without operator intervention and/or down time.

In one example, a print head drop detector (202) is described. The print head drop detector (202) comprises a sampling volume and a fan (208) to cause an airflow though the sampling volume (206). Detection apparatus to detect the presence of non-gaseous material within the sampling volume is also provided.

An additive manufacturing device includes a recoater configured to push powder onto a build platform. The recoater defines an advancing direction for pushing powder. A first baffle is mounted to a first end of a leading edge of the recoater and a second baffle mounted to a second end of the leading edge of the recoater opposite the first end. Each of the first and second baffles includes a base mounted to the recoater, a first wall that extends obliquely ahead of and laterally outward from the base relative to the advancing direction, and a second wall opposite the first wall. The second wall extends obliquely ahead of and laterally inward from the base relative to the advancing direction. A volume is defined between the first and second wall with capacity to collect powder as the recoater advances.

A three-dimensional (“3D”) printing system for printing on a substrate, the printing system including a powder distribution device dispensing powder on the substrate and including a blade-shaped end, the blade-shaped end disposed at a height above the substrate; a powder uniformization device located at a distance from the powder distribution device along a direction substantially parallel to a longitudinal axis of the substrate; one or more sensors disposed upstream from the powder uniformization device and configured to determine one or more parameters of a thickness of the dispensed powder at one or more locations; and a control apparatus configured to determine whether the one or more parameters of the thickness is above a predetermined threshold value, and if the one or more parameters is determined to be above the predetermined threshold value, to adjust the powder distribution device.