Thermomechanical study of combustion synthesized Ti-Ni shape memory alloy

Thermal explosion mode of self-propagating high-temperature synthesis by which time and energy can be saved and the cast product has the least interstitial contamination and the greatest homogeneity is used to successfully produce the Ti-Ni shape memory alloy. The specimens after hot and cold rolling are solution treated and aged. M-s and T-R have their maxima at ageing temperatures of 500 and 450 degrees C, respectively. These temperatures rise with the Ni content. The rate of rise of M-s and T-R in aged specimens depends on the composition so that in the Ti-50.33 at.% Ni alloy, M-s is greater than A(s) while in the Ti-50.23 at.% Ni alloy, the reverse is observed. The rate of variation of M-s and A(s) decreases with increasing ageing temperature when solution treatment is followed by cold working. Under this condition, T-R is greater than that for the specimens without cold working. Cold working strains produce a nonuniform effect on M-s and T-R in aged specimens.