Evaporation of a target, moving with a high speed (~50 m/s) under impact of laser radiation has been investigated. The range of laser power density I = 6÷12 × 106 W/cm2 has been found, at which the pulse mode of the evaporation appears. It is proved theoretically that the occurrence of a discontinuous trace with smoothly varying periodicity is connected with nonlinear character of radiation interaction with the target substance under impact of thermo-chemical mechanisms, in particular, the process of the burning of metal. The developed technique of simultaneous registration of luminosity of a plasma plume in a wide range of intensity allowed the transformation of the recorded signal to distinctly observed micro-pulsations. Observable pulsations correspond in time to the fragment of the print, where the discontinuous trace with varying periodicity is observed.
CO2 laser, laser evaporation, instable oxidation, laser plume