The Macroscopic Phenomena in Plasticity

Abstract

In this paper, the fundamental principles of plastic flow localization are briefly outlined. During the development of plastic flow, there is a changeover in the localization patterns conforming to the corresponding stage of work hardening based on the autowave nature of plastic flow localization. In particular, the evolution of plastic flow from yield point to fracture involves the following four stages of autowave generation: switching autowave → phase autowave → stationary dissipative structure → collapse of autowave. The most intriguing localization pattern is attributed to a phase autowave, which forms at the stage of linear work hardening. The characteristics of the phase autowave (propagation velocity, dispersion, and grain size dependence of the wavelength) have been determined experimentally. Moreover, an elastic-plastic strain invariant is introduced to describe the elastic and plastic properties of the deforming medium, as well as to establish the above characteristics of autowaves. A hypothetic quasi-particle, corresponding to the autowave of localized plasticity, is considered and its potential properties are estimated to interpret the localization process characteristics.