超声波检测焊点质量的建模方法及应用分析

介绍了两层板焊接时焊点的有限元建模方法：通过金相实验得到焊点尺寸参数，利用超声检测的回波衰减理论及超声波传播衰减信号得到焊点阻尼系数。首先建立了材料为BLD的两层板多类型焊点有限元模型，然后通过与设备检测对比的方法验证了模型的准确性，最后研究了探头在曲面检测工况下角度定位的灵敏度问题，并通过实验进行了验证，实验结果表明：对曲面焊点质量进行检测时，探头角度偏离法线10°范围内，检测结果受到的影响很小。

Finite Element Modeling and Application Analyses of Ultrasonic Spot Welding Quality Inspections

This paper described the finite element modeling method which might be used in two layer welding spots: using destructive crystalline phase experiments, the external size parameters of finite element model were obtained, while using ultrasound echo attenuation theory and the ultrasonic detection signal characteristics, the damping coefficients were obtained. The finite element model of two layer welding spot materials was established for the BLD, then, the model accuracy was verified by means of comparisons with equipment inspection, finally the ultrasonic probe's angle positioning sensitivity was analyzed in the body surface detection conditions, and verified by experiments. The results show that when the spot welding of body surface quality inspection, the spot welding detection results will be less affected when the probe angle deviated from the welding spot normal within 10°, sometimes even may be ignored.