焊接残余应力分布情况对焊接构件的安全使用存在一定影响。基于临界折射纵波(LCR)的产生机理和应力检测原理, 搭建了基于声时的应力检测系统。采用“一发一收”的探头布局模式, 探讨了入射角度对LCR 波产生的影响, 利用工件中存在应力会导致LCR 波传播时间变化的现象, 探讨了对接焊缝横向残余应力分布的测试方法。结果表明: LCR 波法检测焊缝残余应力分布与理论分布情况相符。

The welding residual stress distribution is harmful to the safety of the welding structure. Based on the generation mechanism of critical refraction longitudinal wave (LCR) and the principle of its stress detection, a stress detection system based on sound is established. Effect of incident angle on the generation of LCR wave is studied by using the “one emitter and one receiver” probe arrangement, and by using the phenomenon that stress can cause changes the LCR wave propagation time in the workpiece to explore the method for measuring the transverse residual stress distribution in butt welds.The experimental results show that the distribution of residual stress in the welded seam by using LCR wave method is basically consistent with the theoretical distribution.