| 초록 |
We investigated the kinetic behavior and morphological evolution of two-phase microstructures during coarsening using a two-dimensional diffusion-controlled Monte Carlo model. The proposed model controls the ratio of the surface diffusion rate to bulk diffusion rate, and the resultant microstructures and evolution kinetics were investigated. When the surface diffusion is dominant, the model is supposed to mimic the evolution of ligaments during the coarsening of porous metal system, behaving differently from the well-known Kawasaki dynamics. To verify this new model, we calculated a couple of microstructural parameters during coarsening to define the regime of steady state for each simulation instance. Then, we measured the microstructural length parameter to extract the variation of growth kinetic exponent as a function of diffusion rate ratio and system temperature. We found that while Kawasaki dynamics predicts a growth exponent of 4, surface-diffusion-dominant case shows larger values than 4, close to 5. |
