IRON-BASED ALLOY HAVING SHAPE-MEMORY PROPERTY AND SUPERELASTICITY AND METHOD FOR MANUFACTURE THEREOF

摘要

An iron-based alloy having shape memory properties and superelasticity, which has a composition comprising 25-35% by mass of Ni, 13-25% by mass of Co, 2-8% by mass of Al, and 1-20% by mass in total of at least one selected from the group consisting of 1-5% by mass of Ti, 2-10% by mass of Nb and 3-20% by mass of Ta, the balance being substantially Fe and inevitable impurities, and a recrystallization texture substantially comprising a ³ phase and a ³' phase, particular crystal orientations of the ³ phase being aligned, and the difference between a reverse transformation-finishing temperature and a martensitic transformation-starting temperature being 100°C or less in the thermal hysteresis of martensitic transformation and reverse transformation.