NONLINEARITY OF DEFECT INDUCED FREE ENERGY RELEASE AND MULTISCALE MECHANISMS OF ADIABATIC SHEAR FAILURE

摘要

Dynamic strain localization and adiabatic shear failure are studied as specific type of criti-cality in multiscale damage evolution - the structural scaling transition. Specific feature of this transition is the generation of collective modes of defects (auto-solitary waves and blow-up structures) providing dynamic strain and damage localization due to specific non-linearity of free energy release. These modes have the nature of intermediate asymptotic solutions and can be initiated resonansly under dynamic loading in the form of plastic strain and damage localization areas. Dynamic experiments coupled with "in-situ" registration of strain and damage localization dynamics, thermodynamics of localized plasticity and failure, scaling analysis of defect induced structure supported theoretical results concerning leading role of stored energy release in adiabatic shear failure.