Characteristics of Ti50-Pd(50-x)-W(x) High Temperature Shape Memory Alloy
Characteristics of high temperature shape memory alloy in Ti50-Pd(50-x)-W(x) at%, x = 3 and 5 system has been examined. The prepared ingot was homogenized at 1273 K for 86.4 ks followed by water quenched. The homogenized samples were hot-rolled at 1273 K to a plate shape with thickness of 3.5 mm and 1.0 mm. Transformation temperatures were determined by 4-probe electrical resistivity measurement. The transformation behavior in the both samples exhibited similar trend. The first heating curve showed no significant step. In contrast, the first cooling curve exhibited clear step due to martensitic transformation. After second cycle, the transformation behavior was stabilized, thus the clear steps in the cooling and heating curves were seen. Stressstrain curve of hot-rolled plate with 3.5 mm was examined by compression in Ti50-Pd47-W3 at% alloys. The sample exhibited 1 % shape memory effect. By bending test, nearly perfect SME effect was observed in hot rolled Ti50-Pd45-W5 at% alloy plate with thickness of 1 mm.
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
H. Nakayama and M. Taya, "Characteristics of Ti50-Pd(50-x)-W(x) High Temperature Shape Memory Alloy", Materials Science Forum, Vols. 539-543, pp. 3190-3194, 2007