Short Range Ordering and Stabilization of the Martensite Phase in Copper Alloys

Dept. of Applied Physics, Hokkaido University, Sapporo 060, Japan

Abstract

The stabilization phenomenon in martensites due to aging was investigated experimentally and theoretically in Cu-Zn-Al alloys with the aim of clarifying its origin. The martensitic transformation temperatures were measured as a function of aging temperature and time by means of electrical resistivity. The effect of quenching conditions prior to aging was also examined. It was pointed out that two possible causes affecting the stabilization, the long range order and the short range order of alloy structure, can be discriminated according to the tendency of the correlation with the residual resistivity and a time constant of aging effect. It was proposed that the stabilization phenomenon can be caused by the development of the short range order during aging. On the basis of this model, theoretical estimation of the change in the transformation temperature was made. Theoretical values were found to be consistent with the corresponding experimental ones.