Simulation Study on Early Stress Corrosion Damage Detection of Austenitic Stainless Steel Based on Nonlinear Surface Wave

In order to explore the method of detecting the early stress corrosion damage of austenitic stainless steel by nonlinear surface wave, the reconstruction method is used to realize the coupling between stress field and ultrasonic field based on the elastic-plastic deformation constitutive relation by means of ANSYS and ABAQUS finite element numerical simulation software. Furthermore, the influence of micro-crack width and depth, stress direction(tension/compressive) and magnitude on the propagation characteristics of nonlinear ultrasonic surface wave are discussed. The results show that under constant loading, the width of micro-crack is negatively correlated with the nonlinear coefficient, while the depth is positively correlated with the nonlinear coefficient. The micro-crack is widen under the tensile stress, which not only reduces the transmitted surface wave energy, but also weakens the flapping and sliding effects caused by periodic vibration of the interface, so as to inhibit the generation of higher harmonics. Moreover, the critical width of micro-crack decreases with the increase of tensile stress. Compressive stress does the opposite. Therefore, the study on the interaction between the nonlinear surface wave and the micro-crack under constant stress has important engineering application value for the detection of early stress corrosion damage.