Ti60钛合金动态力学行为的J-C本构模型修正研究

    Research on Modification of J-C Constitutive Model for Dynamic Mechanical Behavior of Ti60 Titanium Alloy

    • 摘要: 为了探究Ti60钛合金的动态力学行为,建立合理的本构模型,通过万能试验机和霍普金森压杆装置分别对该材料进行准静态拉伸和动态冲击试验。基于试验获得的应力-应变曲线,对J-C本构模型进行参数标定,探究了其拟合精度和影响因素。依据流动应力的行为特征,建立了一种考虑应变、应变速率、温度相互耦合的修正J-C本构模型,并对其参数进行标定。将修正本构模型的预测值与试验值进行对比分析,借助相关性系数R、平均相对误差系数AARE两个统计参数,对所建立的修正模型的精度进行评估。结果表明:所建立的修正J-C本构模型相关系数R为0.9922,平均相对误差AARE为1.48%,考虑应力、应变和温度的修正J-C模型能合理预测Ti60钛合金的应力流动行为。

       

      Abstract: To investigate the dynamic mechanical behavior of Ti60 titanium alloy and establish a reasonable constitutive model, the quasi-static tensile and dynamic impact tests were conducted using a universal testing machine and a split Hopkinson pressure bar(SHPB) apparatus. Based on the obtained stress-strain curves, the parameters of the original Johnson-Cook(J-C) constitutive model were calibrated, and its fitting accuracy and the influencing factors were examined.Considering the characteristics of the flow stress behavior, a modified J-C constitutive model that accounts for the coupling effects of strain, strain rate, and temperature was developed, and its parameters were determined. A comparative analysis was performed between the predicted values from the modified model and the experimental data. The accuracy of the established modified model was evaluated using two statistical parameters: the correlation coefficient(R) and the average absolute relative error(AARE). The results indicate that the established modified J-C constitutive model achieves a correlation coefficient R of 0.9922 and an AARE of 1.48%. The modified model which incorporates the coupling of stress, strain, and temperature, can effectively predict the flow stress behavior of Ti60 titanium alloy.

       

    /

    返回文章
    返回