The method of residual stress gradient measurement based on ultrasonic technology

According to the theory of elasticity, this paper proposes a new method to measure the residual stress of components based on the critical refraction longitudinal wave (LCR). The expression model of stress in different depth layers was studied, and the residual stress gradient of different layers was detected by ultrasonic probe at different frequency, and the feasibility was verified by using a kind of C-ring experiment. The study shows that the LCR method can be used to measure the residual stress rapidly and accurately, and by changing the frequency of the ring can realize the fast detection of the stress gradient in a certain depth.