2004 Volume 51 Issue 1 Pages 43-47
The Ti-Ni-Cu shape memory alloy by elemental powders was fabricated by using a pulse-current pressure sintering. The influence of Cu content in Ti-Ni-Cu alloys on the microstructures, tensile and thermo-mechanical properties of the sintered compacts was investigated experimentally. The tensile properties of the as-sintered compacts could be fairly improved by performing a solution heat treatment, and the tensile strength and elongation of Ti-40.8at%Ni-9.4at% Cu alloy were approximately 500MPa and 7%, respectively. The deformation resistance of solution heat-treated compact decreased with increasing Cu content, and the yield stress of Ti-36.1at%Ni-14.1at% Cu alloy was 50MPa. The Ti-40.8at%Ni-9.4at%Cu and Ti-36.1at%Ni-14.1at%Cu alloys showed a superelastic-like behavior at a temperature above 333K. The recovery stress of solution heat-treated compact increased with increasing Cu content. The recovery stress of Ti-40.8at%Ni-9.4at%Cu alloy after loading of 2% pre-strain at the temperature change from 293K to 353K was around 350MPa.
