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采用Gleeble-1500D热模拟试验机进行高温等温压缩变形试验,研究了B95оч铝合金在变形温度为330～450℃、应变速率为0.001～1.000 s-1条件下的热变形行为,并利用金相显微镜(OM)和透射电子显微电镜(TEM)分析了B95оч铝合金在不同变形条件下的组织特征。研究结果表明:变形温度和应变速率对B95оч铝合金的流变应力大小有着显著的影响,合金的流变应力随变形温度的升高而降低,随应变速率的增加而增大。B95оч铝合金在450℃以下热变形过程中析出大量的第二相粒子,并随着温度的降低数量显著增加。B95оч铝合金热变形后平均亚晶尺寸随Zener-Hollomon参数的升高而减小,即随着变形温度的降低、应变速率的升高而减小。B95оч铝合金热变形的流变应力行为可以用包含Arrhenius项的Zener-Hollomon参数来描述,其变形激活能为124.09 kJ·mol-1。
The high temperature isothermal compression deformation test was carried out on a Gleeble-1500D thermal simulation tester. The thermal deformation behavior of B95оч aluminum alloy at deformation temperature of 330-450 ℃ and strain rate of 0.001-1.000 s-1 was studied. (OM) and transmission electron microscopy (TEM) were used to analyze the microstructure of B95 оч aluminum alloy under different deformation conditions. The results show that the deformation temperature and strain rate have a significant effect on the flow stress of B95 оч aluminum alloy. The flow stress decreases with the increase of deformation temperature and increases with the increase of strain rate. B95оч aluminum alloy precipitates a large amount of second-phase particles during the thermal deformation below 450 ℃, and the amount increases remarkably with the decrease of temperature. The average subgrain size of B95оч aluminum alloy decreases with the increase of Zener-Hollomon parameters, ie decreases with the decrease of deformation temperature and strain rate. The flow stress behavior of B95оч aluminum alloy during hot deformation can be described by Zener-Hollomon parameters including Arrhenius term. The deformation activation energy is 124.09 kJ · mol-1.