Diffusion in metals

The present state of research in the field of diffusion in metals is described. The currently used methods of studying diffusion processes (the internal friction method, the elastic after-effect method, the method of diffusion pairs, the radioactive isotope method) are listed. The above methods may be used to determine diffusion parameters and to solve various problems in the fields of thermodynamics, kinetics, and diffusion process mechanisms. Attention has been payed to various aspects of dislocation initiation and migration in the diffusion zone, and anealing and surface-active substance effects on these processes. The importance is stressed of multicomponent diffusion research for the proper selection of complex-alloyed steel heat treatment conditions. Diffusion mass transfer processes are of considerable practical interest, since they control the kinetics and mechanisms of phase and structural transformations during processing of metals and alloys as well as the mechanisms of plastic deformation and long-term failure of superalloys