Investigation of Diffusion Processes at Metal Target Irradiation by Pulsed Plasma Flow

Abstract

Pulsed irradiation of metals and alloys by plasma flows and ion beams follows by an emergence of significant temperature gradients and thermo mechanical stresses in near-surface region of a target [1-3]. Processes of heat and mass transfer are intensified. Diffusion is stimulated by temperature growth. Diffusion coefficients are increased on 5-8 orders of magnitude in compare with their stable values, corresponding to the irradiation in continuous regime. A depth of impurity particles penetration doesn’t exceed the value of projectile path length in metals. At deceleration of the impurity particles their collisions with atoms nuclei cause atoms displacement of crystal lattice sites. Because of medium continuity a dominant mechanism of structural damages creation could be atom-atomic collisions cascades, which involve large area, several times exceeding a volume of near-surface region of the target. It is obvious, that the large part of diffusion flow is transferred within displacement cascades [1]...