Microstructural Pattern Formation during Far-from-Equilibrium Alloy Solidification

Abstract

We introduce a new phase-field formulation of rapid alloy solidification that quantitatively incorporates nonequilibrium effects at the solid-liquid interface over a very wide range of interface velocities. Simulations identify a new dynamical instability of dendrite tip growth driven by solute trapping at velocities approaching the absolute stability limit. They also reproduce the formation of the widely observed banded microstructures, revealing how this instability triggers transitions between dendritic and microsegregation-free solidification. Predicted band spacings agree quantitatively with observations in rapidly solidified Al-Cu thin films.

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Cited by in corpus (4)

• Morphological stability of solid-liquid interfaces under additive manufacturing conditions
• Phase-field model of alloy solidification far from chemical equilibrium at the solid-liquid interface
• Mapping of Microstructure Transitions during Rapid Alloy Solidification Using Bayesian-Guided Phase-Field Simulations
• Phase-Field Model of Freeze Casting