Shape Memory Characteristics of Thermoelastic TiNi System Rapid-Solidified Fibers

Abstract

Ti 50 Ni 50-x Cu x ( x＝0, 5, 10, 15 at) fine fibers(diameter＝q80 mm, length＝20 cm～1 m) were successfully developed by the arc melted rapid solidification method. It has been very difficult to do the conventional melt work processing from the bulk material of this alloy to very fine fiber because of the brittleness of the especially in the range of Cu≧8 at. The fibers showed good shape memory effect. As Cu content increased, the temperature hysteresis(＝Af Mf) of recovery strain temperature curves as well as that in the DSC curves became smaller. The tensile strength showed more than 1000 MPa in Ti 50 Ni 40 Cu 10 at. Therefore, the developed rapid solidified, thermoelastic fine fiber actuator/sensor materials have high potential for applications for micro machines and the fillers of smart composites.