双相钢激光拼焊板温拉伸流变应力模型研究

在通过温拉伸实验获得的真实应力-应变曲线的基础上,采用Zener-Hollomon参数的双曲正弦形式来建立双相钢激光拼焊板温拉伸条件下的流变应力模型,方程中材料参数通过最小二乘法线性回归获得,并将其表示成应变的多项式形式,从而使此模型适用于整个应变过程中.流变应力的预测值与实验值吻合较好,预测的最大相对误差为6.27%,最大均方差为8.718MPa,从而验证了双相钢激光拼焊板温拉伸流变应力模型的准确性.

The flow stress mdel of dal pase seel lser tilor wlded banks during wrm tnsion

True stress-train curves of dual phase steel laser tailor welded blanks subjected to warm tensile test have been investigated.The flow stress model of dual phase steel laser tailor welded blanks during warm tension was established by employing the hyperbolic sinusoid function of Zener-Hollomon parameter.Material constants in the equation were expressed in polynomial form of strain and obtained by least-square method.The model was applied to the whole strain process.The stress-strain values predicted by the proposed model well agree with experimental results.The maximum relative error between the predicted and experimental values is only 4.54%,and the maximum mean square deviation is 8.718MPa,which confirmed that it gives an accurate and precise estimate for the flow stress of dual phase steel laser tailor welded blanks during warm tension.