固溶制度对1933铝合金自由锻件组织和力学性能的影响

采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、X射线衍射和室温拉伸研究固溶制度对1933铝合金自由锻件组织和力学性能的影响.结果表明:由于Al_3Zr粒子对晶界的钉扎作用,在470 ℃以下固溶时,合金的再结晶程度很低(＜15%);随着固溶温度升高,再结晶程度逐渐上升;510 ℃固溶时,合金的再结晶程度显著增大(约为48%);1933铝合金锻件中第二相主要有Al_7Cu_2Fe相和η相;合金经470 ℃固溶60 min后,η相溶解比较充分,此后随温度升高或时间延长第二相变化不大;合金的最佳固溶制度为470 ℃、60 min,在此条件下合金具有最好的力学性能.

Effects of solution treatment on microstructure and mechanical properties of 1933 aluminum alloy forgings

The effects of solution treatment on microstructures and properties of the aged 1933 aluminum alloy forgings were investigate by optical microscopy (OM), scanning electron microscopy (SEM), transmission electrical microscopy (TEM), X-ray diffractometry and tensile testing. The results show that the recrystallization fraction is very low (＜15%) when the temperature is below 470 ℃ due to the pinning effect on grain boundaries of Al_3Zr dispersoids. When the forgings are treated at 510 ℃, the recrystallization fraction increases significantly to about 48%. The main phases in this alloy are Al_7Cu_2Fe and η phases. The second phases don't change obviously with increasing temperature and time because the η phase is dissolved almost completely after solution treatment at 470 ℃ for 60 min. The best solution treatment for 1933 alloy forgings is 470 ℃, 60 min, and the alloys under these conditions have the best tensile properties.