Modeling of recrystallization after inhomogeneous deformation

Abstract

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 rate during recrystallization as a function of local deformation has been derived. The analytical model considering the derived nucleation equation is capable of predicting the progress of the recrystallization front as observed in experiments with Titanium Grade 2. The Monte-Carlo model has been developed on the basis of the analytical model. Different functions for the local 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 deformation can be understood. The graded microstructure is a consequence of the combined effect of inhomogeneous nucleation and anisotropic growth of the recrystallizing grains. Experimental grain size gradients were reproduced quantitatively by the present simulations. Agreement was also found for the grain elongation that forms during the recrystallization and grain growth stages.

Modeling the effect of redundant strain factor on the microstructure inhomogeneity of drawn and annealed wire

“…If the change in energy is less than or equal to zero the reorientation is accepted and when the energy is increased the orientation remains unchanged. In the algorithm the reorientation of recrystallized to unrecrystallized one should be stopped [35][36][37].…”

Computer simulation of the effect of post annealing parameters on the microstructure inhomogeneity of the non-uniformly deformed copper

“…Accord to the nucleus density assumed in the previous investigations [5,7,8] for simulating the recrystallization using the Monte Carlo Model, the fraction of lattice sites acting as nuclei is estimated in the order of 10 −2 . Therefore, using Eq.…”

“…If the change in energy is less than or equal to zero the reorientation is accepted and when the energy is increased the orientation remains unchanged. In the simulation the reorientation of recrystallized to unrecrystallized one should be stopped [5][6][7][8][9][10][11].…”

“…Thus, the effects of those should be known, quantitatively, to design a proper annealing program for reducing the inhomogeneity and to obtain the desirable properties in the workpiece. However, there are many works on the simulation the annealing of metals and microstructure evolution during annealing [5][6][7][8][9][10][11][12][13], the effects of annealing parameters on the microstructure inhomogeneity achieved after annealing of the deformed metal has not yet been quantitatively investigated. Therefore, in this paper a computer simulation on the basis of the Finite Element Method (FEM) and Monte Carlo Model (MCM) has been developed to simulate the microstructure of the non-uniformly deformed copper workpiece after annealing and investigate the effects of annealing temperature and time on the microstructure inhomogeneity.…”

Combination of the Upper Bound and Potts Models for Simulation of Microstructure in Wire Drawing and Annealing Processes

“…( . Among the previous works, there are a limited works on the microstructure modeling of drawn wire after annealing (Ref [15][16][17]; however, there are some works on its deformation modeling (Ref 2 -4, 18-22). In the previous works, the effects of wire drawing and annealing parameters on the microstructures of wires have not been investigated, quantitatively.…”