新型Al-Mg-Si-Cu-Zn合金板材组织、织构和性能的优化调控

发布时间：2018-05-17 12:33

  本文选题：Al-Mg-Si-Cu-Zn合金 + 热加工　； 参考：《金属学报》2017年08期

【摘要】：通过OM、SEM、TEM观察以及EBSD和力学性能测试等手段研究了不同热加工工艺对Al-Mg-Si-Cu-Zn合金板材组织、织构和成形性能,以及固溶淬火后等温时效对其析出行为的影响规律。结果表明,2种热加工工艺对T4P预时效态合金的强度和应变硬化指数n基本无影响,但是对平均塑性应变比rˉ、Δr以及不同方向延伸率影响显著;不同热加工过程对合金组织和织构演化均有影响,成形性能较好的固溶淬火态合金板材平均晶粒尺寸略大且呈双模型晶粒尺寸分布特征,其织构组分较多,但是强度较低。对该淬火态合金进行185℃人工时效20 min,其硬度即可升高65 HV,进一步时效到5 h达到峰值硬度132 HV,对应的拉伸性能可达Rp=318 MPa,Rm=364 MPa,A=13%,拉伸断口为典型的塑性断裂。该合金在185℃时效时仍以Mg-Si相析出为主,如b"、b'和Q'相等,峰时效后b"相主要沿b轴方向生长,最后转化为b'和Q'相,合金表现出较好的时效稳定性。
[Abstract]:The effects of different hot working processes on the microstructure, texture and formability of Al-Mg-Si-Cu-Zn alloy sheet were studied by means of TEM observation, EBSD and mechanical properties test, as well as the effect of isothermal aging after solution quenching on the precipitation behavior of Al-Mg-Si-Cu-Zn alloy sheet. The results show that the two hot working processes have no effect on the strength and strain hardening index (n) of T4P preaging alloy, but have significant effects on the average plastic strain ratio (r), 螖 r and elongation in different directions. The microstructure and texture evolution of the alloy were affected by different hot working processes. The average grain size of the solid solution quenched alloy sheet with better formability was slightly larger, and the grain size distribution was similar to that of the double model. The texture composition was more, but the strength was lower. After artificial aging at 185 鈩，

本文编号：1901389