水平与垂直晶界铜双晶的压缩形貌观察与分析

Morphology Observation and Analysis of Compressed Copper Bicrystals in Horizontal and Vertical Grain Boundaries

为了研究晶界方向对铜双晶塑性变形的影响,采用扩散焊方法制备了双晶铜块,通过压缩试验台对水平和垂直晶界方向下的铜双晶进行等形变压缩,对晶界附近变形形貌进行显微观察与分析.结果显示:不同晶界方向对铜双晶的滑移变形有不同的影响;在等压缩形变下,相比于水平晶界双晶体,垂直晶界双晶体滑移线的分布和扩展比水平晶界双晶体的更不均匀,垂直晶界双晶体中晶界附近的应力集中程度更高;垂直晶界双晶体滑移线扩展不连续且有波动性,且孔洞和裂纹数量多于水平晶界,孔洞和裂纹的产生和分布位置更集中于滑移线上或临近滑移线的某一侧.

In order to reveal the influence of grain boundary （GB） orientation on the plastic deformation of copper bicrystals （CB） , first, a CB block was fabricated via the diffusion welding. Then, the equal-strain compression of CB in horizontal and vertical grain boundaries was carried out on a compressing test bed. Moreover, the microscopic morphology near the GB was observed and analyzed. The results show that different grain boundary orientations affect the slipping deformation of CB in different ways, and that, as compared with the CB in horizontal grain boundary, the vertical one is of more uneven distribution and extension of slipping line, higher stress near the GB, discontinuous and waved propagation of slipping line, more holes and cracks whose locations are much closer to or near the slipping line.