5A06铝合金的高温变形行为分析及本构模型研究

Hot deformation behavior analysis and constitutive model study of 5A06 aluminum alloy

采用热模拟实验机对5A06铝合金进行了变形温度为300,350,400,450和500℃,应变速率为0.01,0.1,1和10 s^-1不同热变形条件下的等温压缩实验,分析了变形温度和应变速率对5A06铝合金热变形行为的影响,基于实验数据建立了5A06铝合金的Johnson Cook初始本构模型,并在此模型基础上进行了修正。研究结果表明:5A06铝合金热压缩时的热变形应力与变形温度、应变及应变速率均有关,热变形应力随着应变的增大先快速增大,然后逐步减小直至稳定,随变形温度的升高而降低,随应变速率的增大而增大;与Johnson Cook初始本构模型相比,修正后的本构模型具有更高的预测精度,更能准确地表达5A06铝合金热变形应力与热变形条件之间的关系。

The isothermal compression tests of 5 A06 aluminum alloy under the deformation temperatures of 300,350,400,450,500 ℃and the strain rates of 0.01,0.1,1,10 s^-1 were conducted by the thermal simulation test machine,and the influences of deformation temperature and strain rate on the hot deformation behavior of 5 A06 aluminum alloy were analyzed.Then,the Johnson Cook initial constitutive model of 5 A06 aluminum alloy was established based on the experimental data,and the model was modified.The results show that the hot deformation stress of 5 A06 aluminum alloy during hot compression is related to the deformation temperature,strain and strain rate.With the increasing of strain,the hot deformation stress first increases rapidly,and then decreases gradually until it is stable,it decreases with the increasing of deformation temperature and increases with the increasing of strain rate.Compared with Johnson Cook initial constitutive model,the modified constitutive model has higher prediction precision,the relationship between hot deformation stress and hot deformation conditions of 5 A06 aluminum alloy is expressed more accurately.