Erosion plume dynamics during pulsed laser alloying

Dynamics of erosion plume during pulsed laser alloying (λ = 1.06 μm, pulse duration in millisecond range, power density 105–106 W/cm2) of Fe with Mo, Al, Sn was analysed by means of high speed photorecording. Two qualitatively different types of plume dynamics were found: cylindrical vapour helixes and periodic pulsation. The monitoring of plume dynamics and melt ejection allows one to prevent destruction of the treated surface, to decrease the loss of doping element and to reach its uniform distribution (system: Cr shielding coating-Sn coating-Fe substrate).