Scale-Bridging Thermodynamic and Kinetic Simulation (STKS)
Geometrical grounds of mean field solutions for normal grain growth
R. Darvishi Kamachali, A. Abbondandolo, K. F. Sieburg, I. Steinbach.
Acta Materialia, Elsevier, 90, 252-258, (2015)
The classical mean field approach for normal grain growth in polycrystalline materials is revisited. We re-drive and study possible self-similar solutions and show that the grain size distribution can be determined only by the geometry of neighbouring grains for any given configuration. In three dimensions, it is shown that a single index ⟨r⟩²⁄⟨r²⟩ can represent the geometrical characteristic of grains and has a one-to-one relationship with the mean field parameter γ. We reinvestigate the results of our recent phase-field study in the light of new analytical results and found a value γ≈3.5–3.2 for the stable regime.
Keyword(s): grain growth; grain size distribution; self-similar regime; mean field theory; phase-field simulation