Nonlinear aspects of laser-driven oxidation of metals

Experiments performed in the field of IR laser-induced oxidation of metals and their theoretical explanations are reported. Temperature variations in time of irradiated metallic samples have been recorded with a PC based system capable of evaluating the absorptivity variation function (A(T)) from recorded data. Measurements have been carried out on metals such as vanadium, nickel, tantalum and cobalt at various experimental conditions (power of irradiation, times of exposure, sample size, etc.). Some negative, though mostly positive, feedback existence between thermal and optical degrees of freedom is observed, resulting in stochastic chaotic-type temperature oscillations.