X12合金钢高温拉伸行为及Voce本构模型参数反求方法

High-temperature tensile behavior and reverse method of Voceconstitutive model parameters of X12 alloy steel

为了研究X12合金钢的高温拉伸行为,在Gleeble-1500D热/力模拟试验机上进行了温度为900~1200℃、应变速率为0.01~5 s~(-1)的等温拉伸试验,分析了变形参数对该材料高温拉伸行为的影响规律。为了精确确定材料本构模型参数,提出了一种基于多岛遗传算法的反求优化方法。基于拉伸试验数据,采用提出的本构模型参数反求优化方法建立了X12合金钢Voce本构模型。结果表明,X12合金钢的高温拉伸行为呈现出典型的加工硬化和动态回复特性,其流动应力受到温度和应变速率的显著影响。模型预测值与试验值之间的相关系数、均方根误差以及相对误差分布的期望值和标准偏差分别为0.9933、6.36 MPa、0.3057和6.2998,说明采用反求优化方法得到的X12合金钢Voce本构模型能够准确地预测该材料的高温变形行为。

To study the high-temperature tensile behavior of X12 alloy steel,the isothermal tensile experiments at temperature of 900-1200℃and strain rate of 0.01-5 s-1 were carried out on Gleeble-1500D thermal/mechanical simulation testing machine,and the influence laws of deformation parameters on the high-temperature tensile behavior of the material were analyzed.A reverse optimization method based on the multi-island genetic algorithm was proposed to determine the parameters of the material constitutive model accurately.Based on the tensile experimental data,the Voce constitutive model of X12 alloy steel was established by using the proposed reverse optimization method of constitutive model parameters.The results show that the high-temperature tensile behavior of X12 alloy steel exhibits typical work hardening and dynamic recovery characteristics,and its flow stress is significantly affected by temperature and strain rate.The correlation coefficient,root mean square error and the expected value and standard deviation of the relative error distribution between the predicted values of model and the experimental values are 0.9933,6.36 MPa,0.3057 and 6.2998,respectively,which indicates that the Voce constitutive model of X12 alloy steel obtained by using the reverse optimization method can accurately predict the high-temperature deformation behavior of the material.