Flexural waves generated due to pressure force during the laser induced evaporation process

During the laser ablating of surfaces, the pressure is generated at the interface between the vapor front and the solid substrate. In some cases, the magnitude of the pressure attains considerably high values, which in turn develops a pressure force acting normal to the workpiece surface. The magnitude of the pressure force is sufficient to generate flexural waves propagating along the workpiece. In the present study, a flexural wave generation during laser ablation of steel surface is modeled. The pressure rise at the interface is predicted and the resulting pressure force is determined. The flexural wave characteristics are examined at different locations at the workpiece surface. In order to examine the effect of reflected waves, from the free ends of the workpiece, on the traveling waves radiating boundary conditions on the element sides is considered. It is found that the flexural wave amplitude decays as the location at the surface moves towards the workpiece end. The radiating conditions on the element sides show that the reflected waves have significant effect on the traveling wave characteristics.