Numerical and Experimental Study of Microscale Laser Shock Processing Using Excimer Laser

Microscale Laser Shock Processing (mu LSP) can impart compressive residual stress in Micro Electromechanical Systems (MEMS) components through laser-induced plasma and pressure pulse for improving fatigue performance and wear resistance. The excimer laser was used on mu LSP for shorter wavelength than that in previous researches. The determination method of laser spot size at micro-level spatial resolution was firstly presented. The beam sizes of 20 similar to 200 microns were used at the first time for mu LSP in simulation and experiment. Under these conditions, the characteristic parameters (including plastic deformation and residual stress) were investigated through FEM simulation and laser irradiation experiment, besides the micro-hardness being measured. The experimental results had good agreements with ones of simulation and showed the material performances were remarkably improved after mu LSP.