(中南大学 材料科学与工程学院, 长沙 410083)
摘 要: 采用Gleeble-1500热模拟机进行高温等温压缩实验, 研究了2519铝合金在变形温度为300～450 ℃、 应变速率为0.01～10 s-1条件下的流变变形行为。结果表明： 应变速率和变形温度对合金流变应力的大小有显著影响, 流变应力随温度升高而降低, 随应变速率的提高而增大, 在应变速率 <10 s-1条件下, 流变应力开始随应变增加而增大, 达到峰值后趋于平稳, 表现出动态回复的特征; 而在 =10 s-1, t≥350 ℃的变形条件下, 合金发生了局部动态再结晶。 可用包含Arrhenius项的Zener-Hollomon参数描述2519铝合金高温塑性变形时的流变行为。
关键字: 2519铝合金； 热压缩变形； 流变应力； Zenner-Hollomon参数
2519 aluminum alloy
（ School of Materials Science and Engineering,
Central South University, Changsha 410083, China）
Abstract: The flow stress features of 2519 aluminum alloy were studied by isothermal compression at 300-450 ℃ and strain rate of 0.01-10 s-1 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 strain rate increasing and decreases with deformation temperature increasing. The flow stress of 2519 aluminum alloy increases with strain and tends to be constant after a peak value at strain rates less than 10 s-1, showing dynamic recovery; The flow stress decreases after a peak value with the increase of strain at strain rates of 10 s-1 and deformation temperature higher than 350 ℃, showing partial dynamic recrystallization.The flow stress of 2519 aluminum alloy during high temperature deformation can be represented by Zener-Hollomon parameter including the Arrhenius term.
Key words: 2519 aluminum alloy; hot compression deformation; flow stress; Zener-Hollomon parameter
