Abstract
New microscopic mechanisms of plastic deformation in solids are considered, which are related to phase transitions. Special attention is paid to the relationship between local amorphization processes and deformation micromechanisms in crystalline and quasi-crystalline solids. In particular, theoretical models are proposed, which describe the new deformation micromechanism, related to solid state amorphization, as that capable of causing high-strain deformation in shock-loaded and quasi-statically deformed metallic crystals.