Simulation Research of Metal Defect Detection based on Laser Untrasonic Surface Wave

In this paper, the propagation process of laser-induced ultrasound wave and the mechanism of the defect affecting the sound wave are studied by using the finite element analysis software COMSOL. The simulation results show that the laser irradiation on a metal surface with a certain thickness will produce shear wave, longitudinal wave, head wave and surface wave in the metal. Reasonable setup of waveform receiving point probes in the simulation model can predict the defect location by identifying and calculating the received time domain waveform. From this simulation model, it is known that laser can excite surface waves on the surface of metal materials, and surface waves will propagate along the metal surface. Even if the metal surface has a certain curvature, the surface wave generated by the laser can still be used to detect surface defects of metal materials.