(1. 苏州有色金属研究院有限公司，苏州 215026；
2. 湖南大学 材料科学与工程学院，长沙 410082)
摘 要: 在变形温度为300~450 ℃、应变速率为0.01~10 s−1的条件下，在Gleeble−1500热模拟机上采用圆柱体压缩实验对2026铝合金热变形流变应力行为进行了研究。由试验得出变形过程中的真应力真应变曲线，并利用本构方程对流变应力值进行修正，进而根据修正后的应力值绘制功率耗散图。结果表明：变形过程中的应力值随温度的升高而降低，随应变速率的增大而升高，且修正后的稳态应力值高于未修正值；可用Zener-Hollomon参数的双曲正弦形式来描述2026铝合金热压缩变形时的流变应力行为；高温低应变速率条件下的功率耗散系数最大，该变形区发生了组织转变。
关键字: 2026铝合金；热压缩变形；流变应力；本构方程；功率耗散图
hot compression deformation
（1. Suzhou Non-ferrous Metals Research Institute, Suzhou 215026, China;
2. School of Materials Science and Engineering, Hunan University, Changsha 410082, China）
Abstract:The flow stress behavior of 2026 aluminium alloy under hot compression deformation in the temperature range of 300−450 ℃ at strain rates of 0.01−10 s−1 was investigated by cylindrical compression tests on Gleeble 1500 machine. The true stress—true strain curves were obtained in the tests. The flow stress was corrected by the constitutive equation and the power dissipation map was obtained using the corrected stress. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature. The corrected stable flow stress is generally higher than the uncorrected value. The flow stress behavior of 2026 alloy during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. The efficiency of power dissipation is much higher at high temperature and low strain rate, which is associated with microstructural changes.
Key words: 2026 aluminium alloy; hot compression deformation; flow stress; constitutive equation; power dissipation map
