Abstract:

In order to improve the accuracy of material constitutive equation parameters obtained from cutting experiments, a method to calculate average temperature in primary shear zone was proposed by integrating the temperature distribution equitation based on the moving heat source theory along the shear plane length, combining with the equivalent strain and strain rate calculated from the unequal divided shear zone model. A solution model for material Johnson-Cook(J-C) constitutive equation parameters was established. Through the cutting force and chip thickness data obtained from cutting experiments and genetic algorithm, the parameters in J-C constitutive equation of 300M steel were identified. Compared with the default constitutive model of 300M steel in AdvantEdge FEM software, the accuracy of main cutting forces, thrust forces and chip thicknesses simulated by the new obtained J-C model parameters is improved significantly, which demonstrates the effectiveness of the proposed solution model for constitutive equation parameters.

Key words: identification of J-C parameters, improved temperature model, 300M steel, cutting experiment, FEM simulation

摘要：

为了提高通过切削实验获取材料本构方程参数的精度，提出了将基于移动热源理论的温度分布模型沿剪切面积分计算剪切区平均温度的方法，结合不等距剪切区模型求得等效应变和应变率，建立了材料Johnson-Cook(J-C)本构方程参数的求解模型。根据切削实验获取的切削力和切屑厚度数据并采用遗传算法求得了300M钢J-C本构方程参数。与AdvantEdge FEM软件自带的300M钢本构模型相比，用所求模型参数仿真得到的主切削力、进给力和切屑厚度的精度有显著提高，验证了所建本构方程参数求解模型的有效性。

关键词: J-C参数识别, 改进温度模型, 300M钢, 切削实验, 有限元仿真