Strain-induced defects in solids at the different scale levels of plastic deformation and the nature of their sources

Studies on the mechanisms for deformation of solid surface layers are analyzed based on the notions of physical mesomechanics. It is concluded that peculiarities of a crystalline structure of the solid surface determine specific deformation mechanisms evolving in surface layers of a loaded material at micro-, meso-, and macrolevels. Incompatibility of surface-layer deformation with that of a crystalline sublayer is responsible for a wide range of quasi-periodic profiles of a variable oscillation period and for local zones of bend-torsion emerging at the surface. These zones appear as stress concentrators of different scale levels and generate all the types of stress-induced defects at the surface.