Excess Volume in Materials with Dislocations

The excess volume of edge dislocations and their pileups has been calculated within the framework of the nonlinear theory of irreversible deformations. It has been shown that the existence of a free volume at dislocations is the consequence of the asymmetry of a change in the energy of crystal lattice with respect to the tension or compression. It has been established that the influence of pressure on the plasticity of metals is determined by the value of the excess volume of the major carriers of plastic deformation entering into the defective subsystem of materials. The influence of the excess volume of dislocations on the processes of self-diffusion along the dislocation lines has been examined.