7A85铝合金板材的拉伸应变特征及本构方程

Tensile Strain Characteristic and Constitutive Equation of 7A85 Aluminum Alloy Sheet

摘要: 通过对退火态7A85铝合金挤压板材进行横向热拉伸实验，研究了在不同拉伸温度（200、300、400℃）和不同应变速率（0.001、0.005、0.01 s^-1）下的拉伸应变特征。结果表明，退火态7A85铝合金板材在热拉伸过程中存在着加工硬化和动态回复过程。当应变速率相同时，7A85铝合金板材的抗拉强度随着变形温度的升高而降低，同时当变形温度相同时，板材的抗拉强度随应变速率的增加而增大。通过对热拉伸数据进行线性参数拟合，建立了满足温度和流变应力之间的Arrhenius型本构方程。

Abstract: The tensile strain characteristics of annealed 7A85 aluminum alloy sheet under different tensile temperatures(200, 300, 400 ℃) and different strain rates(0.001, 0.005, 0.01 s^-1)were studied by hot tensile test.The results show that there are work hardening and dynamic recovery processes in the hot tensile process of annealed 7A85 aluminum alloy sheet.When the strain rate is the same, the tensile strength of 7A85 aluminum alloy sheet decreases with the increase of deformation temperature. At the same time, when the deformation temperature is the same, the tensile strength of 7A85 aluminum alloy sheet increases with the increase of strain rate.The Arrhenius type constitutive equation satisfying the relationship between temperature and flow stress is established by fitting the hot tensile data with linear parameters.