(1. 合肥工业大学 材料科学与工程学院，合肥 230009；
2. 成都飞机工业(集团)有限责任公司，成都 610092)
摘 要: 7075铝合金在热变形过程中主要发生连续动态再结晶，在温度为250~450 ℃、应变速率为0.1~1 s-1的条件下，对多组圆柱试样进行热模拟压缩实验。采用金相定量法对热变形后材料的显微组织晶粒度进行测量，建立7075铝合金热变形时动态再结晶晶粒度演化模型。结果表明：根据唯象理论的指数模型，利用线性回归方法求得7075铝合金热塑性变形组织晶粒度的演化模型；将该模型导入到有限元软件中能够预报7075铝合金热变形过程的连续动态再结晶晶粒度；预报结果与实验结果非常接近，说明将该演化模型导入有限元软件中可以较为准确地预测7075铝合金热变形过程动态再结晶晶粒度。
关键字: 7075铝合金；热压缩；连续动态再结晶；有限元；组织晶粒度预报
（1. School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China;
2. Chengdu Aircraft Industrial Corporation, Chengdu 610092, China）
Abstract:Continuous dynamic recrystallization (CDRX) of 7075 aluminum alloy occurs during hot deformation. The thermal compression experiment about the group of cylindrical specimen was done at the temperature of 250-450 ℃ and the strain rate of 0.1-1 s-1. The microstructure grain size of 7075 aluminum alloy was measured by the metallographic quantitative method, the microstructure grain size evolution model of 7075 aluminum alloy. The result shows that, according to the exponential model of phenomenological theory and the linear regression method, the microstructure grain size evolution model of 7075 aluminum alloy during the thermoplastic deformation can be worked out. And then, by the finite element software with the evolution model continuous dynamic recrystallization grain size of 7075 aluminum alloy during hot deformation was predicted. The forecasting result is very close to the experimental one. Therefore, by finite element software with the evolution model, dynamic recrystallization grain size of 7075 aluminum alloy during the hot deformation process can be accurately predicted.
Key words: 7075 aluminum alloy; hot compression; continuous dynamic recrystallization; finite element; microstructure grain size prediction
