Simulating Three-dimensional Phase Coarsening at Ultrahigh Volume Fractions by Phase-field Method

摘要

The dynamics of phase coarsening at ultrahigh volume fraction is studied based on three dimensional phase-field simulations by numerically solving the time-dependent Ginzburg-Landau and Cahn-Hilliard equations. The interesting finding is that the scaling exponent for the kinetics of phase coarsening at ultrahigh volume fraction ( V_V = 0.94) is 2.6. The mierostructural evolution with time at ultrahigh volume fraction is shown. The sealed particle size distribution at ultrahigh volume fraction is also presented. The particle size distribution derived from our simulation at ultrahigh volume fraction is compared with Wagner's three dimensional particle size distribution due to interface-controlled ripening and Hillert's three dimensional grain size distribution in normal grain growth. More particles with flattened edges are formed as a result of particle shape accommodation at the regime of ultrahigh volume fraction.