Study of Aging Kinetics in Copper Based Alloy Martensites

Kinetics of atomic rearrangements during aging of Cu–Zn–Al martensites was investigated to clarify the primary cause of stabilization and rubber-like behavior. Changes in the ordered structure were monitored by X-ray diffraction and residual resistivity measurements. The kinetics of the reordering depends on the pre-aging heat treatments in the parent phase. In the as-quenched sample, both lattice parameters and the resistivity changed significantly by aging at 308 K. In the sample held for 30 s at 373 K prior to aging, the resistivity decreased while the lattice parameters remained constant. The resistivity change in this sample can be attributed to the development of short range ordered structure in the martensite. The correlation between the observed structural change and the stabilization is discussed.