Patent ID: 8083990
Filing Date: 2011-12-27
Classification: C21D,C22C,H01F

Abstract:
1. An iron-based alloy having shape memory properties and superelasticity, which has a composition consisting of 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 2-10% by mass of Nb and 3-20% by mass of Ta, optionally 0.001-1% by mass in total of at least one selected from the group consisting of B, C, Ca, Mg, P, S, Zr, Ru, La, Hf, Pb and a misch metal or 0.001-10% by mass in total of at least one selected from the group consisting of Be, Si, Ge, Mn, Cr, V, Mo, W, Cu, Ag, Au, Ga, Pd, Re and Pt, the balance being substantially Fe and inevitable impurities, and a recrystallization texture substantially composed of a γ phase and a γ′ phase, a frequency of a <100> direction of said γ phase in a cold-working direction being 2 or more, 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.