Advanced phase-field approach to dislocation evolution

Advanced phase-field approach to dislocation evolution

The phase-field approach to dislocations is conceptually advanced. Large strain formulation is developed. A local thermodynamic potential eliminates stress dependence of the Burgers vector and reproduces the desired local stress-strain curve, as well as the desired, mesh-independent, dislocation height for any dislocation orientation. A gradient energy contains an additional term, which exclude...

Phase field approach to interaction of phase transformation and dislocation evolution

Phase field approach to dislocation evolution at large strains: Computational aspects

Computational aspects of the phase field simulations of dislocation nucleation and evolution are addressed. The complete system of equations for the coupled phase field approach to dislocation nucleation and evolution and nonlinear mechanics for large strains is formulated. Analytical solutions for a stationary and propagating single dislocation, dislocation velocity, core energy, and core widt...

Effective Field Theory Approach to Phase Transitions

In this paper I discuss the effective field theory approach, recently developed by Braaten and Nieto in the investigation of quantum field theories at high temperature. I demonstrate that this method can be easily extended to the study of phase transitions in theories with spontaneous symmetry breaking. The first step consists of the construction of a sequence of two effective three-dimensional...

Recrystallization kinetics: A coupled coarse-grained dislocation density and phase-field approach

During recrystallization, dislocation-poor grains grow and invade the heavily deformed dislocation-rich matrix. In this work, we develop a coupled dislocation density and phase-field method to model the isothermal recrystallization process as a phase transformation, driven by the stored elastic energy. Dislocations are represented in two spatial dimensions in terms of a continuous Burgers vecto...