Influence of interface asymmetry on phase partitioning in metal alloys

Abstract

Order and disorder in fragile liquids like undercooled liquid metals are widely explored; however, the effects of in situ structuring, speciation, or partitioning on associated phase change are poorly understood due to challenges in understanding partitioning or speciation in such systems. Here, we demonstrated that migration away from a thermal dynamic invariant point (eutectic) leads to partitioning in metal alloys, resulting in differentiable phase change events. Evolution in heat capacity, enthalpy, and entropy of non-eutectic mixtures was analyzed. Asymmetry in enthalpy dissipation peak during phase transition further confirms this partitioning-driven divergence in entropy change. We infer that, when a liquid metal is not in equilibrium, in situ partitioning, speciation, and segregation can occur, generating new interfaces that abet the undercooling and retention of the liquidous state. This work highlights the role of opposing interfacial stresses and entropy changes in generation of microsystems in non-equilibrium mixtures.