A Study of Common Factors of Plastic Deformation Via a Flow of Point Defects in the Fields of High Local Pressure Gradients in Metallic Materials

In the frame of a quasi-viscous mechanism of plastic deformation via the flows of nonequilibrium point defects in the fields of local pressure gradients, peculiarities of propagation of the front of nanobands of crystal lattice reorientation are studied. A theoretical analysis of the velocities of point defects and the carriers of the rotational deformation mode – nanodipoles of partial disclinations, is made in terms of the type of point defects (vacancies and interstitial atoms), deformation temperature, disclination structure peculiarities and elastically stressed state at the nanoband propagation front. A possibility of simultaneous occurrence of the martensitic and quasi-viscous deformation modes at this front is shown. The effective viscosity coefficient is estimated for different energies of migration activation and temperatures. An important role of high local moments or stress field gradients is revealed during activation of the rotational deformation mode. It is shown that under the conditions of high local stress fields the material viscosity can reach the values close to that of liquid glass.