层错能对铜及黄铜电致塑性效应的影响

Influence of stacking fault energy on electroplastic effect in copper and brass

在退火后的纯铜和H62黄铜样品拉伸过程中施加不同强度的脉冲电流,借助透射电镜观察了不同条件下纯铜和黄铜微观结构的演变。结果表明:层错能较高的纯铜变形过程中主要是位错组态的演变主导,且电流处理后塑性降低;而层错能较低的H62黄铜变形过程主要是孪生主导,电流处理后塑性显著提高。因此,材料本征特性层错能影响着电致塑性效应。

A pulse current with different intensities was applied during the tensile process of annealed pure copper and H62 brass samples, and the evolution of microstructure of the pure copper and H62 brass under different conditions was observed by transmission electron microscopy. The results show that due to the application of electric current, the elongation of the pure copper decreases, while that of the H62 brass increases. The main reason is that the evolution of the dislocation configuration is dominant in the pure copper(with higher stacking fault energy) deformation process, while the H62 brass(with lower stacking fault energy) deformation process is mainly twin dominated. Therefore, the intrinsic characteristic stacking fault energy of the material affects the electroplastic effect.