SHAPE MEMORY ALLOY HAVING TEXTURE AND METHOD FOR ALLOWING THE ABOVE ALLOY TO SHOW SUPERELASTIC EFFECT

摘要

PROBLEM TO BE SOLVED: To provide a steel material or a wire rod having a sufficient shape recovering amt. as-rolled without special operation such as the repetition of thermomechnnical treatment (training treatment) in a shape memory alloy utilizingγ→εmartensitic transformation and to provide a method for allowing the above shape memory alloy to show superelastic effect which has been impossible heretofore. SOLUTION: This is a shape memory alloy contg. iron and manganese and utilizingγ(fcc)→ε(hcp) martensitic transformation. A sheet material having a texture in which the [110] orientationγis preferentially oriented or a wire rod having a texture in which the [110] orientation ofγis preferentially oriented in the longitudinal direction of the wire is applied with strains of <=3% in the [110] orientation of the material in the temp. range of 50 to 175 deg.C.