【摘要】 研究了具有粗、细两种不同晶粒组织状态的MGH956合金板材室温～1200℃拉伸及1100℃持久性能。采用扫描电镜和金相显微镜对拉伸和持久试样的断口形貌及纵剖面组织进行了检验,对比分析了两种板材不同温度下的强化因素、及变形和断裂模式。结果表明:正是由于强化因素、及变形和断裂模式上的不同,使得细晶板材的拉伸强度在低温高于粗晶板材,在高温则低于粗晶板材,以及细晶板材的持久强度大大低于粗晶板材;但两种板材从室温～1200℃的拉伸伸长率并无明显差异。更多还原

【Abstract】 Room temperature to 1200 ℃ tensile and 1100 ℃ stress to rupture properties of MGH956 alloy sheets with coarse and fine grained structure were studied.Fracture morphologies and longitudinal section microstructure of tensile and stress to rupture specimens tested at different temperatures were examined by SEM and metallograph.Strengthening factors,deformation and fracture mode of the two kinds of sheet at different temperatures were comparatively analyzed.Results show that it is due to the differences of strengthening factors,deformation and fracture mode that result in that tensile strength of the fine grained sheet is higher at low temperature and lower at high temperature than that of the coarse grained one,as well as stress to rupture strength of the fine grained sheet is much lower than that of the coarse grained one,but tensile ductility of the both is no more different from room temperature to 1200 ℃.更多还原