In spite of its outstanding properties, Y-TiAl use as lightweight structural material for high temperatures applications is still limited by difficulties of its processing by classical metallurgy. Although powder metallurgy seems more convenient, its application by classical route imposes special consolidation methods as Y-TiAl powder has poor compressibility and sinterability. At SHS processing from elemental powders a-TiAI_3 and a_2-Ti_3AI form first, having lower Gibbs Free Energy of Formation, ΔG°_f, than TiAI. The present research proved that, in an equiatomic Ti-AI powder mixture, they can further react with Ti/AI in excess forming TiAI - reactions also having negative ΔG°_f. An intimate component mixture and an activation energy are necessary for this purpose, which can be assured by a controlled mechanical alloying prior SHS. Appropriate parameters of MA and SHS been established, able to assure y-TiAl obtaining of quite full density, high homogeneity and fine microstructure.
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