How to apply the phase field method to model radiation damage

The phase field (PF) method provides a valuable means of predicting radiation induced microstructure evolution of domains ranging roughly from 100 nm to 100 μm in size and for lengths of time ranging from microseconds to years, depending on the rate of diffusion. In this work we summarize how to apply the PF method to modeling radiation damage. We begin by summarizing the PF method, and discuss the numerical solution of the PF equations. We then summarize approaches for representing the free energy of defects within a material. Next, three PF approaches for representing extended defects are discussed: the Wheeler, Boettinger, and McFadden model, the Kim, Kim, Suzuki model, and the Grand Potential model. We use a simple 1D void growth problem to compare the predictions of these models, as well as their computational expense. We end by describing how defect generation, recombination and annihilation at sinks can be described by the PF method, as well as discussing modifications required to model nucleation.