Ti-Ni-Cu shape memory alloys were fabricated using powder metallurgy process. The elemental powders in chemical compositions of Ti49.8Ni50.2-xCux (x= 5, 10, 15, 20) were mixed by planetary ball mill at 500 rpm for 0.3 ks and were sintered using pulse current pressure sintering equipment. The influence of Cu content on shape memory properties of sintered alloys was investigated. Increase of Cu content provided narrower transformation hysteresis and lower yield stress. The constant load thermal cycling test showed that the Ti49.8Ni35.2Cu15 alloy has the narrowest transformation hysteresis comparable to that of the wrought materials of 9 K, and the alloy has clearly two-step martensitic transformations.
展开▼
