FEM Simulation Study on Nondestructive Test of Surface Cracks with Laser Ultrasonics

Recently developed laser ultrasonic technique has many applications in industrial sectors, such as laser ultrasound velocity and attenuation measurements, NDT and E and measurement of grain sizes of materials. The technique with an optical detection system enables one to fabricate a genuine remote sensing system that can be deployed in hostile environments. A 2D finite-element numerical simulation has been developed to investigate the generation of ultrasonic waves in a homogeneous isotropic elastic slab under a line-focused laser irradiation. We, further, carried out the FEM simulation to study the propagation and scattering characteristics of the laser ultrasounds in the case of surface cracks