A three-dimensional (3D) metal object manufacturing apparatus has a plurality of thermally insulative members that float in a volume of heat transfer lubricating fluid in which a X-Y translation mechanism moves to position a platform opposite an ejector. The apparatus also includes a housing having an internal volume in which the platform and X-Y translation mechanism are located. The heat transfer lubricating fluid can be a molten salt, such as a molten fluoride, chloride, or nitrate molten salt. The thermally insulative members can be spheres made of zirconium oxide or zirconium dioxide. The thermally insulative layer formed by the members floating in the fluid protects the X-Y mechanism while the housing helps keep the surface temperature of the object being formed on the platform in an optimal range for bonding of melted metal drops ejected from the ejector to a surface of a metal object being formed on the platform.

This disclosure describes an additive manufacturing method that includes monitoring a temperature of a portion of a build plane during an additive manufacturing operation using a temperature sensor as a heat source passes through the portion of the build plane; detecting a peak temperature associated with one or more passes of the heat source through the portion of the build plane; determining a threshold temperature by reducing the peak temperature by a predetermined amount; identifying a time interval during which the monitored temperature exceeds the threshold temperature; identifying, using the time interval, a change in manufacturing conditions likely to result in a manufacturing defect; and changing a process parameter of the heat source in response to the change in manufacturing conditions.

A printing apparatus for printing a three-dimensional object comprising an operative surface, at least one supply hopper for depositing layers of powder onto the operative surface and an energy source for emitting at least one energy beam onto the layers of powder. The supply hopper and energy source are configured such that when a topmost layer of powder is being deposited onto an underlying layer of powder on the operative surface, the direction travelled by the supply hopper when depositing the topmost layer is different to the direction travelled by the supply hopper when depositing the underlying layer, and at least one energy beam is emitted onto the topmost layer and at least one further energy beam is emitted onto the underlying layer, simultaneously, to melt, fuse or sinter the topmost and underlying layers.

A printing apparatus for printing a three-dimensional object comprising an operative surface, at least one supply hopper for depositing layers of powder onto the operative surface and an energy source for emitting at least one energy beam onto the layers of powder. The supply hopper and energy source are configured such that when a topmost layer of powder is being deposited onto an underlying layer of powder on the operative surface, the direction travelled by the supply hopper when depositing the topmost layer is different to the direction travelled by the supply hopper when depositing the underlying layer, and at least one energy beam is emitted onto the topmost layer and at least one further energy beam is emitted onto the underlying layer, simultaneously, to melt, fuse or sinter the topmost and underlying layers.

A device produces three-dimensional objects layer by layer in a powder bed fusion process. The device includes a building space, at least one energy source, a building area with a building space platform and a building space container laterally confining the building space platform. The building space platform has an upper side, facing a powder, and an underside, facing away from the powder. The upper side of the building space platform includes a material with a thermal conductivity of at least 20 W/(m.Math.K) and the underside of the building space platform includes a material with a thermal conductivity of a maximum of 0.5 W/(m.Math.K). The contact surface of the upper side of the building space platform with respect to the powder or with respect to the cooling medium is raised by at least 20% in comparison with the planar surface of a building space platform.

A device produces three-dimensional objects layer by layer in a powder bed fusion process. The device includes a building space, at least one energy source, a building area with a building space platform and a building space container laterally confining the building space platform. The building space platform has an upper side, facing a powder, and an underside, facing away from the powder. The upper side of the building space platform includes a material with a thermal conductivity of at least 20 W/(m.Math.K) and the underside of the building space platform includes a material with a thermal conductivity of a maximum of 0.5 W/(m.Math.K). The contact surface of the upper side of the building space platform with respect to the powder or with respect to the cooling medium is raised by at least 20% in comparison with the planar surface of a building space platform.

A three-dimensional shaping device includes a chamber that has a shaping space; a heating unit configured to heat the shaping space; a base that has a shaping surface exposed to the shaping space; a discharge unit configured to discharge a shaping material toward the shaping surface while moving in a first direction in the shaping space heated by the heating unit and shape a three-dimensional shaped article; a first drive unit configured to move the base in a second direction crossing the first direction; and a tubular first heat resistant member that is disposed between a peripheral part of a first opening formed in a partition wall of the chamber and the base, configured to extend and contract in the second direction in accordance with a movement of the base in the second direction, and defines a separation space separated from the shaping space, in which at least a part of the first drive unit is disposed in the separation space.

A three-dimensional shaping device includes a chamber that has a shaping space; a heating unit configured to heat the shaping space; a base that has a shaping surface exposed to the shaping space; a discharge unit configured to discharge a shaping material toward the shaping surface while moving in a first direction in the shaping space heated by the heating unit and shape a three-dimensional shaped article; a first drive unit configured to move the base in a second direction crossing the first direction; and a tubular first heat resistant member that is disposed between a peripheral part of a first opening formed in a partition wall of the chamber and the base, configured to extend and contract in the second direction in accordance with a movement of the base in the second direction, and defines a separation space separated from the shaping space, in which at least a part of the first drive unit is disposed in the separation space.

A sintering composition, consisting essentially of: a solvent; and a metal complex dissolved in the solvent, wherein: the sintering composition contains at least 60 wt. % of the metal complex, based on the total weight of the sintering composition; and the sintering composition contains at least 20 wt. % of the metal of the metal complex, based on the total weight of the sintering composition.

An internal defect detection system for a three-dimensional additive manufacturing device which performs additive molding by emitting a laser beam to a powder bed is provided. This system specifies a candidate position of an internal defect on the basis of a change amount of a local temperature measured in an irradiated part of a powder bed irradiated by a laser beam. The system calculates a cooling speed at the candidate position on the basis of a temperature distribution and determines whether an internal defect exists on the basis of the cooling speed.