冷轧高纯铝柱状晶粒的组织与微取向的不均匀性

Inhomogeneities of microstructures and micro-orientations in cold-rolled high purity Al columnar grains

采用光学显微术与SEM-EBSD技术观测了经65%压下量冷轧后高纯铝多晶体中不同取向柱状晶粒的微观组织与微取向图.结果表明:形变晶粒各部分具有不同的转动趋势,靠近晶界部分(BP)的转动角度小于远离晶界部分(IP)的;〈001〉∥RD取向的晶粒向α-取向线聚集,其BP与IP部分的转动角度相差5°～6°;〈121〉∥ND取向的晶粒向β-取向线聚集,其BP和IP部分的转动角度相差5°～12°;这表明轧制变形晶粒各部分的微观组织与微取向分布与其初始取向和所处位置有关.

Deformation microstructures and micro-orientations in columnar grains with different orientations in a polycrystalline high purity Al cold-rolled up to 65% （thickness reduction） were investigated by optical microscopy （OM） and SEM-EBSD techniques. It is found that rotations are inhornogeneous within the individual grains, the rotation angles of the parts close to the initial boundaries （BP） are smaller than those remote from the boundaries （IP）, as the deviation angles between the BP and IP are 5°- 6° in the grains with （001）∥RD orientation leading to the rotation along the α-fiber, while the deviation angles are 5°- 12° in the grains with （121）∥ND orientation rotating toward the β-fiber. These results demonstrate that the microstructures and local rotations of various parts within the rolled individual columnar grains are influenced by their initial orientations and localities.