Numerical simulation of laser-generated ultrasonic waves for identification of branched-breaking defects

Abstract In order to detect stress corrosion cracking (SCC) type defects, this paper uses the finite element method (FEM) to simulate the branched-breaking defects and use the laser-generated ultrasonic wave to detect the branched-breaking defects. The branched-breaking defects often influence the reflection and mode conversion of ultrasonic wave. When the branch surface defects are at the top of the slot, the maximum amplitude of the R-wave signal spectrum gradually increases as the angle of the branch defect decreases. However, when the branch surface defects are at the center of the slot, the Rayleigh wave (R-wave) has the same characteristics and the maximum amplitude of the R-wave signal spectrum are much lower than the branch defects are at the top of the slot. The proposed method may provide an useful way to identify and distinguish the branched-breaking defects.