SYNERGETIC APPROACH TO WORK-HARDENING OF METALS

Work hardening is understood as a transient stage that starts at the onset of plasticity and approaches steady state. The process of hardening, which is a consequence of generation of dislocations, their clustering and annihilation, is described in terms of a simple synergetic model of the dislocation population. The population is spontaneously arranged into a characteristic dislocation pattern of high and low dislocation density regions, where the wavelength and profile of the pattern change during deformation. In the steady state all newly generated dislocations are annihilated in the high density regions. The work-hardening process can be understood as the tendency of a deformed metal to minimize its internal energy.