An experimental study has been performed in order to characterize the metallic materials ablation by means of interaction between impulsional laser beam and matter for 248 nm, 308 nm, 532 nm, and 1.064 micrometers . The ablation is achieved on a static sample (oxidized stainless steel alloy), with one or several successive pulses and for different energy densities. It permits us to determinate the ablation fluence threshold according to each wavelength and the alteration of the surface as a function of the number of pulses. The aim of this application consists in measuring the superficial oxidized layer and quantifying the necessary fluence to ablate a part or all of it. In 248 nm-light, it has been determined that we need 28 J/cm2 and 20 successive pulses to remove the totality of the 10 micrometers depth superficial oxidized layer. Other experiments have been realized under the gaseous cover of argon. We hope to avoid oxidation. The efficiency of ablation doesn't seem clearly better than in ambient air. Peripheral oxides redepositions exist as in ambient air.
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