Synthesis of nanocrystalline half-Heusler TiNiSn by mechanically activated annealing

Mechanically activated annealing was employed successfully for the synthesis of nanocrystalline half-Heusler (TiNiSn) alloy for the first time. TiNiSn could be synthesized by annealing, after 5 h of mechanical alloying of equiatomic elemental blend, at a temperature as low as 600 °C in 2 h. The nanocrystalline nature and resultant increased surface area coupled with large number of defects induced by mechanical alloying has resulted in a significant reduction in temperature and time of annealing in comparison to earlier reports (800 °C–400 h). This could lead to energy efficient low temperature synthesis of nanocrystalline half-Heusler alloys for thermoelectric and magnetic applications.