A phase-field simulation of nucleation from subgrain and grain growth in static recrystallization

A new recrystallization phase-field method is proposed, in which the three stages of recrystallization phenomena, i.e., recovery, nucleation and nucleus growth are sequentially taken into account in a computation. From the information of subgrain patterns and crystal orientations in a polycrystal that are obtained by a dislocation-crystal plasticity FE analysis based on a reaction-diffusion model, subgrain groups surrounded by high angle boundary are found out. Next, subgrains in the group are coalesced into a nucleus by rotation of crystal orientation and migration of subgrain boundaries through a phase-field simulation. Then a computation of nucleus growth is performed also using the phase-field method on account of an autonomic incubation period of nucleation, in which stored dislocation energy assumes a role of driving force. It is shown that the present method can numerically reproduce the three stages of recrystallization as a sequence of computational procedure.