Formation of micro-, submicro- and nanocrystalline structures in nickel-base alloys

Regularities of structure formation in nickel base alloys subjected to various types of strengthening in a wide temperature-strain rate interval of deformation have been studied systematically. The character of operating mechanisms of plastic deformation and recrystallization and their interaction with processes of second phase dissolution and precipitation have been analyzed. It has been established that a microduplex type microcrystalline structure is resulted from transformation of a subgranular structure to a granular type and concurrent transformation of partially coherent interphase boundaries to non-coherent boundaries. It has been shown that during severe plastic deformation the process of structure formation is a step by step character.