Modeling of recrystallization after inhomogeneous deformation

Recrystallization in an inhomogeneously predeformed material (a cold-drawn cylindrical rod) is described by an analytical model and simulated with the Monte-Carlo technique. For this purpose, an equation for the nucleation ra te during recrystallization as a function of local deformation has been der ived. The analytical model considering the derived nucleation equation is c apable of predicting the progress of the recrystallization front as observe d in experiments with Titanium Grade 2. The Monte-Carlo model has been deve loped on the basis of the analytical model. Different functions for the loc al deformation were introduced, and recrystallization and subsequent grain growth were simulated. With the aid of simulation, the formation of both a grain size gradient and large elongated grains in the region of critical de formation can be understood. The graded microstructure is a consequence of the combined effect of inhomogeneous nucleation and anisotropic growth of t he recrystallizing grains. Experimental grain size gradients were reproduce d quantitatively by the present simulations. Agreement was also found for t he grain elongation that forms during the recrystallization and grain growt h stages.