柱状晶Al在冷轧过程中微观组织演变的定量表征Ⅱ.微观分裂

摘要原始取向为{001)(uv0)的柱状晶Al样品分别冷轧到10％，30％和50％，采用EBSP技术定量表征了不同取向晶粒基带内的微观分裂．结果表明晶粒均都分裂为胞块组织，不同取向晶粒变形后的微观组织结构不同．随应变量的增加GNBs取向差增加，并满足2／3指数关系．Frank公式分析表明，胞块界面中的位错主要来自由Schmid因子决定的激活滑移位错．

MICROSTRUCTURAL EVOLUTION OF COLUMNAR GRAIN Al DURING COLD ROLLING II. Mircoscopic Subdivision

Columnar grain Al samples with {001} (uv0} orientations were cold rolled to reductions of 10%, 30% and 50%, respectively. The microscopic subdivision of the matrix bands in grains with different orientations was quantitatively characterized in detail by using EBSP technique. It is found that all the grains are microscopically subdivided into dislocation cell blocks. But the microstructures of differently oriented grains are different after rolling. With increasing strain, the misorientation angles across the dislocation boundaries increase, following a power relationship with an exponent of 2/3. By the Frank formula, the dislocations in the dislocation boundaries are mainly from the slip systems decided by the Schmid factors.