Characteristics of the martensitic transformation in the low-alloyed Ti-Ni alloys

The effects of small additions of Cr, Cu, Al, and cycling numbers (1-100 cycles) on the martensitic-transformation temperatures, hysteresis, microhardness and shape-recovery degree have been investigated for near-equiatomic Ti-Ni alloys. Non linear dependence of the martensitic points vs concentration of the alloying elements is observed. The transformation hysteresis decreases with an active of the alloying element quantities (except Cu). Microhardness grows up to 25 cycles and then does not change. Shape recovery degree in these alloys reaches 100 %. The causes of influence of the alloying elements on the parameters of the martensitic transformation are discussed.