Materials Science Forum, Vol.394-3, 495-498, 2001
Effect of heat treatment on the properties of Ti-25Ni-25Cu (at%) SMA melt-spun ribbons
Amorphous Ti-25Ni-25Cu(at%) shape memory alloy (SMA) melt-spun ribbons were heat-treated at various temperatures in order to achieve different micro structures. The properties of the ribbons, i.e. shape memory characteristics, deformation behavior and microstructures were characterized by means of differential scanning calorimetry (DSC), tensile tests, thermal cycling tests under constant stresses and transmission electron microscopy (TEM). It was found that the as-spun ribbon was amorphous with a high yield stress of 1.35GPa at room temperature. The specimens are brittle when the heat-treatment temperature is below 1023K. It is also found that the ductility of the ribbons was improved by heat-treatment at 1073K.