深冲铝板坯冷轧显微组织、织构与力学性能

COLD-ROLLED MICROSTRUCTURES, TEXTURES AND MECHANICAL PROPERTIES IN DEEP DRAWING ALUMINIUM PLATE

研究了不同冷轧工艺参数的深冲铝板坯（wA1＞99．75％）的显微组织、织构，测定了不同方向的力学性能；由D－500全自动X射线衍射仪建测极图，按Bunge的方法计算取向分布函数（ODF）；通过透射电镜观察变形显微结构．结合冷轧变形亚组织结构和织构特征，讨论了位错胞结构与板坯塑性变形和力学性能的关系，以及对板坯塑性各向异性的影响，预测材料深冲性能．分析认为，材料力学性能决定于变形组织结构和织构，随冷变形量增大，位错缠结胞变形并发生取向排列形成显微带，使材料产生力学性能各向异性及加工硬化．本研究显微组织和织构特征及力学性能分析结果表明，接近50％冷轧变形量的板坯中变形亚组织均匀、多种织构混存，有利于降低材料深冲制耳率．并经工业制罐试验验证．

The evolution of the microstructure and texture of cold rolled pure aluminium (99. 75 %) plate at different strains have been investigated. The mechanical properties of the plate at different angles in rolling direction were measured by uniaxial tensile testing. The pole figures were determined with D500 X--ray diffraction goniometer and ODF's were calculated by Bunge's method. The microstructures were studied by TEM. In those cases, the correlation among the microstructural anisotropy, the development of microbands and textures has been discussed. The deep drawing property was predicted.It is indicated that the mechanical properties depend on the textures and microstructures. When the dislocation cells develop into strip structure and emerge in a direction, the anisotropy of the specimens and the resistance of plastic deformation increase with further cold working. It is found that the deformation microstructure (cell structure) distributes homogeneously in about the same size and dislocation density at about 50% cold--rolling. The copper texture and cube texture rotating around Normal Direction can be determined, which is beneficial to deep drawing deformation.