Abstract: An additive manufacturing system with a build chamber has a halide vessel that generates a halide gas and a dissociation chamber with a filament. Metal condensate is contacted with the halide gas to form a gaseous metal halide compound. The gaseous metal halide compound is decomposed to deposit metal on the filament. In an example, titanium reacts with gaseous iodine to form gaseous titanium tetraiodide.

Abstract: Byproduct condensate generated during additive manufacturing is controlled by providing at least one electrode inside a chamber. The condensate may be electrically charged as it is generated or an electrical charge may be imparted to the condensate. The electrode may have either a positive or negative bias to either attract or repel the condensate. The electrode may be located on a wall of the chamber or associated with a transparent window through which a laser beam passes into the chamber.

Abstract: Surface and sub-surface defects are removed during additive manufacturing. After a layer of an object is formed in a powder bed, a portion of the layer is removed while the object is in the powder bed to remove surface and or sub-surface defects. The removal step may be performed on a layer-by-layer basis. A directed energy beam or tool may be used to remove a shallow object-powder interface portion of the layer, or a deeper skin portion of the layer. In this way, the completed object may be removed from the powder bed substantially free of surface roughness and sub-surface defects.