Laser shock processing of Al-SiC composite coatings

Laser shock processing (LSP) is a technique of surface treatment (similar t o shot peening) in which laser-induced mechanical shocks develop compressiv e stresses in the material. The stresses are of sufficient intensity. to mo dify microstructure and properties of the coatings. In the present study, l aser shocks of power density of 5 to 8 GW/cm(2) power density, generated by means of a neodymium-glass laser, were used to treat Al + SiC composite co atings deposited by means of a HVOF spraying technique, The laser processed samples were metallographically prepared, and their microstructure was inv estigated by optical microscope and SEM. The latter was also used to invest igate the surface morphology of the laser treated specimens, Finally, the m icrohardness and oscillating wear resistance of the coatings were tested an d compared to data obtained for as-sprayed samples.