基于电磁超声的塑性损伤铝材抗拉强度预测

针对电磁超声信号信噪比低这一问题,在利用相对非线性系数预测抗拉强度的同时引入应力三轴度来提升塑性损伤试件抗拉强度预测的准确性.建立了电磁超声非线性检测塑性损伤试件的有限元三维仿真模型,计算两个特征参量:应力三轴度和相对非线性系数,研究试件的内部应力状态特征和电磁超声检测信号的频谱特征.仿真分析结果表明这两个特征参量敏感...

Prediction of tensile strength of plastic damaged aluminum based on electromagnetic ultrasound

Aiming at the problem of low signal-to-noise ratio of electromagnetic ultrasonic signals,the relative nonlinear coefficient is used to predict the tensile strength,and the stress triaxiality is introduced to improve the accuracy of the prediction.A three-dimensional finite element simulation model for the electromagnetic ultrasonic nonlinear detection of plastic damaged specimens is established.Two characteristic parameters:stress triaxiality and relative nonlinear coefficients are calculated.The simulation analysis results show that the sensitivities of the two characteristic parameters to different damage stages are different.The stress triaxiality is more sensitive to the late stages of plastic damage,while the relative nonlinear coefficient is more sensitive to the early damage.An experimental platform for electromagnetic ultrasonic non-linear detection of plastic damaged specimens is established,and the electromagnetic ultrasonic detection of different plastic damaged specimens is performed.The relation of tensile strength with relative nonlinear coefficient and the relation of tensile strength with stress triaxiality for different plastic damaged specimens are further quantified.According to the sensitivity of the characteristic parameters to damage,the combination of the two characteristic parameters can improve the prediction accuracy in predicting tensile strength.