Femtosecond laser shock peening of galvanized stainless steel

In this paper a SUS316L stainless steel was electroplated with metallic layers and coated with polymer films. A sub-100fs ultrashort laser pulse with a central wavelength of λ=800nm was utilized to process the layer. The aim was to generate shock waves due to ablation of the deposited sacrificial layers. Generated shockwaves propagate and penetrate the lower stainless-steel sample and increase its mechanical hardness (Laser Shock Peening). The sacrificial layer protects the sample from ablation damage and determines the shock wave coupling. To achieve maximal peening, we compare different sacrificial layers and laser processing parameters.