Stress induced martensitic transformation in aged titanium nickel single crystals

The orientation dependence of mechanical behavior of Ti-51at.%Ni single crystals as a function of structural state and test temperature has been investigated. It has been shown that mechanical properties (ductility, strain localization, martensite structure and superelasticity effect) of solution treated single crystals principally are different from those in polycrystals of close composition. Strong orientation dependence of ductility in B2-phase and in the temperature interval of stress induced martensitic transformation has been found. It is detected that strong influence of precipitates on kinetic of martensitic transformation development and on structure of martensite and thus on superelasticity behavior occurs.