工程机械用Q1100钢的热变形应变补偿本构方程

Thermal deformation strain compensation constitutive equation for Q1100 steel for construction machinery

采用Gleeble?3800热模拟试验机研究工程机械用Q1100钢在变形温度为850~1200℃、应变速率为0.01~10.00 s?1条件下的热变形行为,建立恒定应变与应变补偿的Arrhenius本构方程。研究结果表明:随着变形温度升高、应变速率减小,Q1100钢的流变应力降低,真应力?真应变曲线发生由动态回复型到动态再结晶型的转变;随应变增加,参数α和n先减小后趋于平缓,Q和lnA先减小后增大,其六次多项式拟合效果较好,相关系数R均在0.98以上;流变应力预测值与实验值的相关系数为0.99266,绝对误差在15 MPa内的数据点有92.13%,平均相对误差为5.25%,验证了模型的准确性。

The hot deformation behavior of Q1100 steel for construction machinery at deformation temperature of 850?1200℃and strain rate of 0.01?10.00 s?1 was studied by Gleeble?3800 thermal simulator.Arrhenius constitutive equation of constant strain and strain compensation was established.The results show that the flow stress of Q1100 steel decreases with the increase of deformation temperature and the decrease of strain rate,and the flow stress curve changes from dynamic recovery to dynamic recrystallization.The parametersαand n decrease first with the increase of strain and then tend to be gentle.Q and lnA decrease firstly and then increase with the increase of strain,and the sixth-order polynomial fitting effect is good,and the correlation coefficient R is above 0.98.The error analysis shows that the correlation coefficient between the predicted value of the strain stress and the experimental value is 0.99266,the data point with absolute error within 15 MPa is 92.13%,and the average relative error is 5.25%,which verifies the accuracy of the model.