Concentration Characteristics of Diffusion-Induced Recrystallization

Abstract

Diffusion-induced recrystallization (DIR) is investigated in Au/Cu and Ag/Pd thin-film interdiffusion couples. It is experimentally demonstrated that several generations of new grains are formed inside the diffusion zone by a cascade-like process. Each generation is distinguished by a characteristic composition level. In order to understand the observed composition levels quantitatively, a thermo-mechanic model has been derived, which determines the thermo-elastic driving force to the grain boundary. By the model, it is shown that those grains dominate the diffusion zone, which develop the maximum possible stress in front of the moving boundary.