Grain boundary diffusion and plasticity/superplasticity of polycrystalline and nanostructured metals and alloys

The characteristic features of diffusion and diffusion controlled processes in polycrystalline metals and alloys with bcc and fcc crystal lattice during annealing and creep are examined. Consideration is given to the interrelated processes of diffusion, grain boundary sliding/migration, which determine plastic deformation development at specified conditions. The distinctive features of grain boundary diffusion of substitution impurity from coating are investigated for nanostructured metals and alloys and the respective coarse grain counterparts. The manifestations of low temperature and/or high strain rate superplasticity in nanostructured metals and alloys are considered.