Preparation of γ-TiAl Alloys via Self-Propagating Aluminothermic Reduction-Slag Washing Refining Coupled with Vacuum...

Conventional titanium alloy production based on the Kroll process features high energy consumption and long procedures, making low-cost, short-process fabrication a research focus in titanium metallurgy. In this work, low-interstitial γ-TiAl alloys were prepared via a coupled self-propagating high-temperature synthesis (SHS)-slag washing refining-vacuum arc remelting (VAR) process using TiO₂ as the raw material. Slag washing refining was performed at 1750 °C with 150 g of CaO-Al₂O₃-SiO₂-CaF₂ mold flux and 1.5 wt.% Ca, followed by VAR under a vacuum of 10^-2-10^-3 Pa. γ-TiAl alloy with a composition of Ti 66.01 ± 0.5 wt.%, Al 33.8 ± 0.5 wt.%, O 0.054 ± 0.002 wt.%, N 0.046 ± 0.005 wt.%, and C 0.085 ± 0.008 wt.% was obtained, and the inclusion size was refined to 0-3 μm. This coupled approach provides a scalable, low-cost route for the industrial preparation of low-interstitial γ-TiAl alloys.