Methodologies and manufacturing processes to manufacture components by electron beam melting additive manufacturing, particularly components of molybdenum or a molybdenum-based alloy and particularly of complex nuclear component geometries. Input parameters are provided for controlling electron beam melting additive manufacturing equipment, such as electron beam melting machines. The input parameters relate to various process steps, including build set-up, initial thermal treatment, initial layering of powder, pre-consolidation thermal treatment, consolidation, post-consolidation thermal treatment, indexing of layers, and post-build thermal treatment. The methodologies and manufacturing processes allow manufacture of components of molybdenum having a purity of ≥99.0% and a density of ≥99.75%. Metallographic cross-sections of the manufactured molybdenum components were porosity-free and crack-free.

A device (1) for the generative production of a three-dimensional object (2) by selectively solidifying construction material layers made of solidifiable construction material (3) layer by layer in a successive manner using at least one laser beam (5), comprising at least one device (4) for generating at least one laser beam (5) in order to selectively solidify individual construction material layers made of solidifiable construction material (3) layer by layer. The device (4) comprises at least one laser diode element (10) that is arranged or can be arranged directly over the construction plane (9) on which solidified construction material layers or construction material layers to be solidified are selectively formed and is designed to generate a laser beam (5) directed directly onto the construction plane, and/or the device (4) comprises at least one laser diode element (10) and at least one optical element (27).

A method for forming a three-dimensional article through successive fusion of parts of a powder bed comprising: providing a model of the three dimensional article, applying a first powder layer on a work table, directing an energy beam over the work table causing the first powder layer to fuse in selected locations according to the model to form a first cross section of the three-dimensional article, applying a second powder layer on the work table, directing the energy beam over the work table causing the second powder layer to fuse in selected locations according to the model to form a second cross section of the three-dimensional article, wherein the second layer is bonded to the first layer, detecting a local thickness in at least two positions in at least the second powder layer, varying an energy beam parameter depending on the detected local thickness of the second powder layer.

Aspects of the disclosure are directed to additively manufacturing a three-dimensional structure. As may be implemented in accordance with one or more embodiments, a plurality of stacked layers are deposited, and for one or more respective layers of the plurality of stacked layers, pores are formed within the layer by applying pulsed energy to the layer. The pulsed energy is used to create a space sealed within the layer and having an inner surface defined by material of the layer.

An additive manufacturing system including a two-dimensional energy patterning system for imaging a powder bed is disclosed. The two-dimensional energy patterning system may be used to control the rate of cooling experienced by each successive additive layer. Accordingly, the system may be used to heat treat the various additive layers.

An additive manufacturing system including a two-dimensional energy patterning system for imaging a powder bed is disclosed. The two-dimensional energy patterning system may be used to control the rate of cooling experienced by each successive additive layer. Accordingly, the system may be used to heat treat the various additive layers.

An additive manufacturing system including a two-dimensional energy patterning system for imaging a powder bed is disclosed. The two-dimensional energy patterning system may be used to control the rate of cooling experienced by each successive additive layer. Accordingly, the system may be used to heat treat the various additive layers.

An apparatus includes a build plate, a powder application apparatus that applies metal powder onto the build plate to form a powder layer, a beam irradiation apparatus that irradiates the powder layer with an electron beam, and a control unit that controls the powder application apparatus and the beam irradiation apparatus. When the powder layer is preheated by irradiation with the electron beam, the control unit sets a beam size and an irradiation position of the electron beam such that lines of the electron beam do not overlap each other at least at a start of preheating, and controls the beam irradiation apparatus to gradually increase at least one of a beam current and the beam size of the electron beam from the start of preheating to an end of preheating.

A nozzle according to one embodiment has an inner surface and an outer surface, and is provided with a first passage through which an energy ray passes, and a second passage that is provided between the inner surface and the outer surface, and through which powder and fluid pass. The second passage includes a second open end on one end thereof in a first direction. A first surface that is one of the inner surface and the outer surface includes a first edge on one end thereof in the first direction. A second surface that is the other one of those includes a second edge on one end thereof in the first direction, and is distanced from the first edge toward the first direction. The fluid ejected from the second open end flows along the second surface, and separates at the second edge.

An additive manufacturing apparatus includes a platform, a dispenser configured to deliver a plurality of successive layers of feed material onto the platform, at least one light source configured to generate a first light beam and a second light beam, a polygon mirror scanner, an actuator, and a galvo mirror scanner. The polygon mirror scanner is configured to receive the first light beam and reflect the first light beam towards the platform. Rotation of the first polygon mirror causes the light beam to move in a first direction along a path on a layer of feed material on the platform. The actuator is configured to cause the path to move along a second direction at a non-zero angle relative to the first direction. The galvo mirror scanner system is configured to receive the second light beam and reflect the second light beam toward the platform.