Diffusive phase transformation in a Cu–Zn alloy under rapid heating by electropulsing

Abstract

Electropulsing with a damped oscillating waveform was employed to heat cycle a Cu–Zn alloy containing α and β′ phases. It was found that significant long-range diffusion and then a diffusive phase transformation α + β′→β can occur in the alloy during the course of heating, even when the heating rate during the electropulsing treatment is very high (10⁶ K s⁻¹). The phenomenon is different from the common cases of rapid heating and rapid cooling. It implies that electropulsing can dramatically enhance diffusion in the alloy.

Acknowledgements

Financial support by The National Natural Science Foundation of China (grants 90206044 and 50371091) and The National Major Basic Research Development Program Item of China (grant G1999065009) is acknowledged. The authors thank Professor Lu Ke and Wang Yuanming for many helpful discussions.