EFFECT OF CHEMICAL-COMPOSITION AND HEAT-TREATMENT ON THE SHAPE-MEMORYPARAMETERS IN THE TINI-ME ALLOYS

The TiNi-Me shape memory alloy parameters (namely, phase transformatio n ''strength yield'', recoverable strain, reversion stress, material h ardness) have been investigated as a function of the chemical composit ion, heat treatment regimes and deformation condition. These parameter s are found to Ire structurally sensitive ones both to the macroscopic and microscopic structure of the material. Their response to heat tre atment regimes is usually non-homogeneous function of the aging temper ature and time variatior. Effects of doping and secondary particle pre cipitation are of great importance. Some recommendations for the choic e of the SMA chemical composition and final heat treatment regime can be proposed.