THERMOMECHANICAL TREATMENT FOR SHAPE MEMORY ALLOY AND SHAPE MEMORY ALLOY MEMBER

摘要

PURPOSE: To provide a shape under constraint, as a shape at a martensitic-phase temp., by applying shape memory treatment and constraining heat treatment to a member made of shape memory alloy consisting of specific percentages of Ni, Cu, and Ti under respectively specified conditions. ;CONSTITUTION: Shape memory treatment (length, L₀), consisting of heating up to 400-650°C for 0.5-120min, is applied to a member made of a shape memory alloy having a composition consisting of, by weight, 45-50% Ni, 5-12% Cu, and the balance Ti. Further, this member is subjected to constraining heat treatment consisting of heating in a state under constraint (length, L₁) up to a temp. exceeding the transformation heat treatment temp. and cooling in the constrained state. By this method, a shape under constraint (length, L₂) can be provided as a shape at a martensitic-phase temp., and the recovery when this member is heated up to a temp. not lower than the transformation temp. can take the value of (L₀-L₂) as working distance.;COPYRIGHT: (C)1994,JPO&Japio