Effects of Transformations of Grain Boundary Defects on Diffusion in Nanocrystalline Materials


The specific features of diffusion processes in nanocrystalline materials are discussed. Theoretical models are suggested that describe the effects of transformations (climbing, splitting) of grain boundary dislocations and disclinations on self-diffusion in nanocrystalline materials. It is shown that climbing of grain boundary dislocations strongly enhances diffusion processes in nanocrystalline materials, causing the self diffusion coefficient to be increased by several orders.