The crystallographic texture, phase composition and evolution, and nanohardness of a Ti–45Al–2Cr–5Nb alloy processed by selective laser melting (SLM) at various substrate preheating temperatures were investigated. The α2 phase decreases whereas the γ and B2 phases increase with increasing preheating temperature, and the relationship in orientation between B2, α2 and γ phases is described as follows: . The SLM-processed TiAl alloy shows much higher nanohardness than its traditional casting counterpart, which increases with the increase of preheating temperature. The findings would be a valuable reference for fabricating TiAl components with acceptable texture, phase compositions and nanohardness by SLM.

This article originally appeared in  Scripta Materialia 118, 2016, Pages 13–18.