Facile synthesis of fine Ti–Al intermetallic compound powders via sodiothermic reduction in molten CaCl2

Fine powders of titanium aluminides, the Ti–Al intermetallic compounds were directly synthesized via sodiothermic reduction of TiO2/Al2O3 composites in molten CaCl2. By using uniformly ball milled TiO2/Al2O3 composites, all types of titanium aluminides (Ti3Al, TiAl and TiAl3) were successfully synthesized in strictly single phase of the all product powders. Through this synthesis method, the composition of Ti–Al alloy powders is tunable in the entail range of the binary system, and the all composition is uniformed in the all particles. The average particle size of the product powders was in the range of some hundreds of nanometers. The oxygen content in the product powders was proportional to its specific surface area, and was reduced down to less than 1500 ppm when reacted at 1373 K for 72 h. [Display omitted] •Direct synthesis of Ti–Al intermetallic compound fine powders from TiO2/Al2O3.