挤压态42CrMo钢热压缩应力-应变关系的变参数Arrhenius模型研究

Study on Variable Parameter Arrhenius Model of Thermal Compression Stress-strain Relationship of Extruded 42CrMo Steel

为了研究挤压态42CrMo高强度钢的高温流变行为,使用Gleeble1500热物理模拟机在温度1123~1348K和应变速率0.01~10s^(-1)下进行了等温热压缩实验,采集了真应力-应变数据。引入修正的变参数型Arrhenius本构方程,在不同真应变下进行了多元线性回归拟合,获得了方程中各参量(变形激活能Q、材料常数n、α及结构因子A)随应变的变化规律。构建出了挤压态42CrMo高强度钢的高温流变应力本构方程。对实验和预测结果之间的相对误差进行了计算。结果表明:模型最大相对误差为4.73%,最大平均误差为1.34%。

In order to study the high temperature flow behavior of 42CrMo high strength steel, the isothermalcompression tests at 1123-1348 K and the strain rates of 0.01-10 s-j were carried out by using Gleeblel500 thermal physicssimulator. True stress-strain data were collected. Leading into modified variable parameter Arrhenius constitutive equation,multivariant linear regression fitting was carried out under different true strain. The changing laws of the parameters （deformedactivation energy Q, materials constant n, a and structural factor A） with the strain were obtained. The constitutive equation ofthe high temperature flow stress of 42CrMo high-strength steel was constructed. The relative error between the experimentaland predicted result was calculated. The results show that the maximum relative error of the model is 4.73%, while themaximum average error is 1.34%.