Additively-manufactured refractory metal component, additive manufacturing process, and powder

An additive manufacturing process for producing a component, the method comprising:

• providing a starting powder with particles composed of at least one material selected from the group consisting of molybdenum, a molybdenum-based alloy, tungsten, a tungsten-based alloy, and a molybdenum-tungsten-based alloy;
• providing the starting powder with at least one of the following:
• particulates having a melting point above a melting point of a matrix phase of the component, the particulates configured to function as crystallization nuclei for a molten matrix phase to achieve a fine-grained microstructure of the component;
• at least one precursor substance for particulates, wherein the melting point of the particulates lies above the melting point of the matrix phase and the particulates composed of the at least one precursor substance are formed during layer-wise fusing of the particles of the starting powder using a laser or electron beam, the component being formed from powder particles fused selectively by the laser or electron beam to form a solid structure;
• at least one component which in reaction with at least one component of a process gas atmosphere during layer-wise fusing of the particles of the starting powder using a laser or electron beam forms particulates having a melting point above the melting point of the matrix phase;
• layer-wise fusing the particles of the starting powder with a laser or electron beam to form the component with a matrix phase having a molybdenum content, a tungsten content or a total content of molybdenum and tungsten greater than 85 at %;
• and
• manufacturing the component in a build direction in the additive manufacturing process and, in a plane parallel to the build direction, a grain extent parallel to the build direction having an average grain aspect ratio of more than 2 and less than 5.