METHOD FOR SHAPE MEMORIZING TREATMENT OF TI-NI SHAPE MEMORY ALLOY

摘要

PURPOSE:To regulate the shape recovering temp. of a shape memory alloy without deteriorating its recovering capacity by constraining the shape of a Ti-Ni shape memory alloy having a specified compsn. into a prescribed one, heating it to a specified temp., thereafter gradually cooling it to a temp. corresponding to a desired shape memorizing temp. and executing rapid cooling. CONSTITUTION:A Ti-Ni shape memory alloy contg. Ni or furthermore contg. one or = two kinds among Ni-substituting elements such as Fe, Co and Cr by =3 at % in total, in which the total content of Ni and Ni-substituting elements is regulated, by atom, to 49.7 to 52.0 and the balance substantial Ti is prepd. This alloy is formed into a prescribed shape and is heated to the temp. range of 470 to 530 deg.C as its shape is constrained into the above one. Next, the alloy is gradually cooled from the above temp. to a one corresponding to a desired shape recovering temp. Af' at about =10 deg.C/min gradual cooling rate, is thereafter rapidly cooled and is subjected to shape memorizing treatment. In this way, the regulation of the shape memorizing temp. is enabled without deteriorating its recovering capacity.