Heat and mass transfer under non-stationary external influence

The paper presents results obtained in the framework of mass and heat transfer studies carried out in two limiting cases corresponding to a small and anomalously large value of the pulse power. These condition correspond to the high energy excitations of the crystal lattice. In the case of a large pulse power, Fick's law are unable to describe kinetic processes. The data on structural changes in the metal, characteristic of the pulsed thermal exposure caused by a giant laser pulse in the Q-switched mode, are presented. Experimental results establish that under conditions of high-speed metal deformation both accelerated transfer processes-mass and heat-share a common nature. An additional contribution to heat transfer is considered as energy transfer by a directed flow of edge dislocations. The estimates of energy transferred by dislocations, obtained using the Frenkel-Kontorova (FK) equation, corresponded well to the results of the laser flash method experiments. A mass transfer is studied both the fixation of the final static concentration of the transported atoms and through the results of thermophysical studies. The Peierls stress was calculated.