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以铜单晶为模型材料，采用扫描电镜电子通道村度术（SEM－ECC）和透射电子显微技术，在不同尺度上研究了单次和两次等通道转角挤压（equalchannelangularextrusion，ECAB）过程的剪切形变特征，结果表明（1）一次ECAE挤压产生的剪切形变取向与理论预测相接近，但剪切形变表现出局部化特征，出现了微观尺度上的剪切带；（2）两次ECAE产生的两套剪切带间存在着交互作用，导致剪切带出现分叉现象，方向也与理论预测结果有所偏差，但仍能保持其各道次的剪切特征；（3）第2次ECAE后，剪切形变的不均匀性得到改善，组织更加细化，而且相邻亚晶取向差也有所增大。
Using single-crystal copper as the model material, single-pass and double-pass equal channel coupled pressure (ECAB) processes were studied on different scales by scanning electron microscopy (SEM) and transmission electron microscopy The results show that (1) the shear deformation orientation induced by a ECAE extrusion is close to the theoretical prediction, but the shear deformation shows localized features and the shear band at the microscopic scale appears. (2) The interaction between the two sets of shear bands produced by two ECAEs resulted in the bifurcation of the shear band and the deviation from the theoretical prediction results, but still maintained the shear characteristics of each pass. After ECAE 2, the heterogeneity of shear deformation was improved, the organization was more refined, and the adjacent sub-crystallographic orientation difference also increased.