DIFFUSION-INDUCED GRAIN-BOUNDARY MIGRATION IN AL-ZN SYSTEM

The analysis of mechanism and kinetics of the diffusional zinc penetra tion along the moving grain boundary during diffusion induced grain bo undary migration (DIGM) has been performed in aluminium samples deposi ted with zinc. The anisotropy of a new Zn-enriched grain emerging duri ng DIGM has been observed. This anisotropy results from both the chang e of migration distances and Zn-content in the new grain with regard t o the plane of original grain boundary. The zinc profiles within DIGM zone have been discussed based on Hillert's criterion. It has been sho wn that the shape of zinc profiles is modified by the increasing contr ibution of the volume diffusion, especially at the higher annealing te mperatures.