NONLINEAR ASPECTS OF LASER-DRIVEN OXIDATION OF METALS

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