抄録
The martensitic and the reverse transformation temperatures are directly related to the bending rigidity of the TiNi shape memory alloy (SMA) wire. In this paper, aiming at obtaining a functionally graded TiNi shape memory alloy wire that varies in bending rigidity from high to low along the wire axis, a new fabrication process of combined powder metallurgy and plastic working is proposed. First, a multi-layered TiNi green compact, where Ti-Ni compositions varied layer by layer, was sintered by means of spark plasma sintering process, and then it was hot-extruded into a wire. In this paper, we investigated functionally graded properties of deformation properties of the extruded wires. According to tensile test, it is found that the wire having both shape memory effect and superelasticity was successfully fabricated because functionally graded properties of transformation temperatures still retain even in the hot-extruded wire.
