Laser Removal of Contaminants on the Metal Surface

Abstract

A Q-switched Nd:YAG laser with a 532 nm and 450 mJ/pulse was employed to study the decontamination characteristics of Type 304 stainless steel specimens and aluminum specimens artificially contaminated with CsNO3, Co(NH4)2(SO4)2, Eu2O3 and CeO2, respectively. The relative atomic molar percent of the contaminants on metal surface before and after laser irradiation was determined by EPMA. The morphology of specimen surface was examined by SEM. The ablation behavior of contaminants on Type 304 stainless steel specimens was investigated for the decontamination variables such as a number of laser shots, laser fluence and an irradiation angle. Their optimum values were found to be 8, 13.3 J/cm2 and 30°, respectively. The removal of contaminants on aluminum surface, however, was found to be more difficult by laser.