采用拉伸试验、硬度和残余应力测试等方法研究了固溶保温时间对6061铝合金中厚板力学性能和表面残余应力的影响; 采用光学显微镜、透射电镜、X射线衍射仪对其组织和织构进行观察分析; 在单滑移晶体塑性模型基础上, 以Schmidt因子为桥梁计算分析了板材织构组态对力学性能和残余应力的影响规律。结果表明: 固溶时间从2 h延长到4 h, 该中厚板在厚度方向的组织更加均匀, 表层和心部各织构的取向密度差异更小, 厚度方向的力学性能更均匀, 表面残余应力更小; 固溶保温时间导致淬火残余应力变化原因是固溶保温会影响织构变化, 从而引起Schmidt因子加权平均值的变化。

Effects of solution treatment time on mechanical properties and surface residual stress of 6061 thick aluminum alloy plates were investigated by tensile, hardness and residual stress tests. The microstructure and crystallographic texture of 6061 aluminum alloy plates were observed and analyzed by optical microscopy, transmission electron microscopy and X-ray diffraction. Then the influence of crystallographic texture on mechanical properties and residual stress distribution were analyzed with the Schmidt factor based on single slip crystal plasticity model. The results show when the solution treatment time prolonged from 2 h to 4 h, the microstructure and the mechanical properties along thickness became more homogeneous, the orientation density difference between surface and core, and residual stress were smaller. The difference of residual stress of the plate is ascribed to evolution of crystallographic texture, which associated with solution treatment time. That causes change of the weighted mean value of Schmidt factor.