Phase-field modelling of solute trapping during rapid solidification of a Si-As alloy

TL;DR

This paper introduces a phase-field model to study solute trapping during rapid solidification of a Si-As alloy, providing a new definition of the partition coefficient that aligns well with experimental data.

Contribution

A novel phase-field approach with a new partition coefficient definition improves modeling of solute trapping at high growth velocities.

Findings

Better agreement with experimental data at high velocities

New definition of nonequilibrium partition coefficient

Enhanced understanding of rapid solidification processes

Abstract

The effect of nonequilibrium solute trapping by a growing solid under rapid solidification conditions is studied using a phase-field model. Considering a continuous steady-state concentration profile across the diffuse solid-liquid interface, a new definition of the nonequilibrium partition coefficient in the phase-field context is introduced. This definition leads, in particular for high growth velocities, to a better description of the available experimental data in comparison with other diffuse interface and sharp-interface predictions.