A theory of non-equilibrium grain boundaries and its applications to nano- and micro-crystalline materials processed by ECAP

The basic principles and methods of a non-equilibrium grain boundary theory are presented. A new approach for describing non-equilibrium grain boundaries in nano- and microcrystalline metals processed by equichannel angular pressing (NMC-ECAP metals) is proposed. To illustrate the opportunities of this theory use, a number of examples are presented describing the evolution of NMC-ECAP metals defect structure, taking into account the non-equilibrium grain boundary state. In particular, NMC-ECAP materials grain growth abnormalities, internal friction regularities and high strain rate superplasticity characteristic features are explained.