Research on The Optimal Sound Path of LCR Wave Detection Method and The Optimal Thickness Range of The Tested Sample

Residual stress is a very important factor among many factors such as structural failure and fracture of key components of mechanical structures. It is necessary to study accurate measurement and characterization techniques for residual stress. The LCR (Longitudinal critically refracted) wave method has the characteristics of non-destructiveness, high efficiency and accuracy, and has high application value in industrial stress detection. In the LCR wave method, the sound path and the thickness of the tested sample will affect the time-of-flight obtained by the subsequent cross-correlation algorithm, resulting in inaccurate final stress detection values. In this paper, the ultrasonic nondestructive testing system is used to detect the sound path of different sizes and the thickness of the tested sample, and the sound path range and the thickness range of the tested sample for the LCR wave method are obtained. The obtained experimental results promote the development of non-destructive testing technology.