Quantitative multi-phase-field modeling of non-isothermal solidification in hexagonal multicomponent alloys

A quantitative multi-phase-field model for non-isothermal and polycrystalline solidification was developed applied to dilute multicomponent alloys with hexagonal close-packed structures. The effects of Lewis coefficient undercooling on dendrite growth were investigated systematically. Results show that large coefficients facilitate the release latent heat, which can accelerate while suppress tip radius. greater initial undercooling, stronger driving force growth, faster rate dendrites, higher solid fraction, more serious solute microsegregation. simulated dynamics are consistent predictions from phenomenological theory but significantly deviate classical JMAK neglects soft collision effect mutual blocking among dendrites. Finally, taking Mg-6Gd-2Zn (wt.%) alloy as an example, morphology shows good agreement experimental results.