A phase-field model to simulate the formation of both void and gas bubble superlattices is derived from a grand potential functional, assuming 1D diffusion of self-interstitial atoms. The model is capable of accounting for superlattice formation by either a nucleation and growth or spinodal decomposition mechanism; in this work, we focus on the nucleation and growth mechanism, using a discrete nucleation approach in the phase-field model. In simulations of void formation, short aligned rows of voids were initially formed, followed by growth in the size of the aligned rows, and finally leading to superlattice formation, consistent with experimental observations....
Sublattice Kim-Kim-Suzuki Model
The phase-field method has been established as a de facto standard for simulating the microstructural evolution of materials. In quantitative modeling the assessment and compilation of thermodynamic/kinetic data is largely dominated by the CALPHAD approach, which has produced a large set of experimentally and computationally generated Gibbs free energy and atomic mobility data in a standardized format: the thermodynamic database (TDB) file format. Harnessing this data for the purpose of phase-field modeling is an ongoing effort encompassing a wide variety of approaches....