Evolution of the grain structure of metals and alloys under severe plastic deformation: continuum models

Products made of metals and alloys with a fine-grained structure, which have high physical, mechanical operational characteristics, are becoming increasingly in demand many technical technological fields. The most common efficient technologies for the production parts from this class materials various processes severe plastic deformation (SPD) (in general practice, at low homologous temperatures). At same time, to achieve degrees deformation, significant part require increased processing temperatures, undergo heating during processes, may be accompanied by changes grain subgrain structure due recovery recrystallization processes. An empirical approach development SPD modes that ensure formation necessary requires huge time financial costs, therefore considerable attention is paid researchers field solid mechanics metal forming approaches methods mathematical modeling. In connection foregoing, number publications on subject has been intensively growing recent years. currently known models differ significantly their approaches, depth penetration into physics scope consideration. proposed brief review focused qualitative analysis works topic, preliminary classification existing according purpose, versatility, functionality. It seems possible single out two describing change thermomechanical alloys: continual cases, single-level) multilevel, based introduction internal variables physical theories. This devoted consideration first these approaches. Until now, macrophenomenological continuum experimental data conducted both laboratories macrosamples real conditions. Models usually formulated form operator relations over quantities, they relatively easy implement “embedding” widely used commercial software packages, but costs experiments identify models, characterized degree versatility. Continuous theories less common, still often used. These description mechanisms evolution terms variables.