INFLUENCE OF SURFACTANTS ON HEAT AND MASS-TRANSFER IN MELTING OF THE SURFACE OF A SUBSTANCE BY A LASER-PULSE

It is shown theoretically and numerically that the convective flow reg imes during melting of the surface of a substance by a laser depend on the relationship between dimensionless thermocapillary and concentrat ion - capillary numbers, that an inhomogeneity of the distribution of surfactant particles and unsteady surface heating may give rise to a m ultivortex structure of surface flows, and that the development of mul tivortex flows facilitates deeper penetration of an alloying substance into a laser melt.