Phase-field model for solidification of a eutectic alloy

摘要: In this paper we discuss two phase-field models for solidification of a eutectic alloy, situation in which liquid may transform into distinct solid phases. The first is based on regular solution model the with chemical miscibility gap. This suffers from deficiency that, sharp interface limit, it approximates free-boundary problem surface energy solid-solid zero and consequently mechanical equilibrium at trijunction requires that has dihedral angle (locally planar). We propose second uses order parameters to distinguish phase provide thermodynamically consistent derivation ensures local entropy production positive. conduct asymptotic analysis liquid-solid transition show governed by both kinetics are present. Finally, consider stationary between phases phase, recover condition interfacial tensions (Young's equation). compares favourably numerical solutions appropriate trijunction.