Critical Refraction Longitudinal Wave Detection for the Distribution of Residual Stress in Butt Weld of Steel

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.