Microstructure and phase composition of the Nb-Si based in-situ composite from plasma spheroidized powder

Mechanical alloying with subsequent plasma spheroidization is a novel technological route to produce the new powder materials for additive manufacturing technologies, such as selective laser melting and direct laser fabrication. Nb-25Ti-2Cr-2Al-2Fe-16Si (at.%) powder synthesized by mechanical alloying and plasma spheroidization. The spheroidized powder with uniformly chemical elements distribution was sieved for 71–125 μm and used for spark plasma sintering. The sintered specimen consists of 5 phases – continuous Nbss, with dispersed Nb5Si3, NbFe4Si, Ti5Si3, and Ti. The formation of the Ti and Ti5Si3 phases is associated with an excess Ti content in the chemical composition, which was previously suppressed by rapid cooling during plasma spheroidization.