An Atomistic\nInvestigation of the Inverse Coarsening\nProcess by the Phase-Field Crystal Model

Coarsening is a very common phenomenon that has a crucial\nimpact\non the average grain size and properties of materials. However, our\ncurrent understanding of coarsening is mainly based on the mean-field\ntheories or ex situ observations, and the influence of transient process-related\nphenomena, such as grain rotation, inverse growth, etc., on coarsening\nwas not considered. In this work, we simulated the coarsening process\nof supported nanograins by a phase-field crystal (PFC) model. Our\nsimulations show that the inverse coarsening phenomenon might occur\nunder the influence of the substrate, where small grains grow at the\nexpense of the large ones. We found that the substrate-induced grain\nrotation has a significant effect on the appearance of inverse coarsening,\nand the average size growth velocity of inverse coarsening is far\nslower than that of normal coarsening. Furthermore, the influences\nof initial grain size, misorientations, pinning potential strength,\nand the lattice mismatch on the coarsening of biocrystal systems are\ndiscussed in detail.