This paper presents the results of an experimental program investigating the ablation of oxides from copper alloy surfaces using a frequency doubled Nd:YAG laser. A collection of coins with similar levels of surface oxidation were cleaned using range of laser pulsing parameters on dry, wet and submerged surfaces. It was discovered that laser cleaning was always associated with one of two types of coin surface damage. At higher powers the damage took the form of surface melting and at lower powers the incident laser beam converted the original oxide layer into adherent droplets of molten metal.
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