Rapid synthesis of dense NiTi alloy through spark plasma sintering of a TiH2/Ni powder mixture

Dense NiTi alloy was prepared by liquid phase spark plasma sintering from a TiH2 and Ni powder mixture at 1050 °C for 4 min. Dehydrogenation of TiH2 in the powder mixture was rapidly completed after heating to 850 °C. The sintered alloy showed no obvious transformation peaks, whereas the homogenized alloy, thermally treated in Ar at 1150 °C for 2 h, displayed clear transformation peaks with a high transformation enthalpy of 10.6 J/g. The hardness of the sintered and homogenized alloys were statistically the same.