Al-8.4Zn-2.2Mg-2.4Cu合金高温压缩变形的流变应力

Flow Stress Behaviors of the Elevated Temperature Compression Deformation for Al-8.4Zn-2.2Mg-2.4Cu Alloy

在Gleeble 1500热模拟试验机上,采用高温等温压缩试验,研究了Al 8.4Zn 2.2Mg 2 4Cu铝合金在250～450℃温度范围及1.0～0.001s-1应变速率范围内压缩变形的流变应力变化规律。结果表明,应变速率和变形温度的变化强烈地影响着合金的流变应力,流变应力随变形速率的提高而增大;随变形温度的提高而降低;其流变应力值可用Zener Hollomon参数来描述。从流变应力、应变速率和温度的相关性,得出了该合金高温变形的四个特征常数。

The flow stress of the compression deformation for Al8.4Zn2.2Mg2.4Cu alloy in the temperature range of 250～450℃ and strain rate range of 1.0～0.001s-1 were studied by isothermal compression with Gleeble1500 simulated machine. The results show that the flow stress is controlled by strain rate and deformation temperature, the flow stress increases with increase of strain rate and decreases with increase of temperature. The flow stress of the alloy during hightemperature deformation can be described by ZenerHollomon parameter. Four characteristic constants of the alloy during plastic deformation at high temperature were derived from the interdependencies of flow stress, strain rate and temperature.