Effect of rigid body motion in phase-field models of solid-state sintering

TL;DR

This paper compares phase-field models of solid-state sintering with and without rigid body motion, highlighting the importance of advection terms for accurate shrinkage rate predictions and exploring their effects through simulations.

Contribution

It introduces a detailed analysis of rigid body motion effects in phase-field models and demonstrates the necessity of advection terms for size-independent shrinkage rates.

Findings

Inclusion of advection term leads to size-independent shrinkage rate.

Rigid body motion significantly affects equilibrium and kinetic properties.

Sensitivity analysis reveals parameter impacts on model behavior.

Abstract

In the last two decades, many phase-field models for solid-state sintering have been published. Two groups of models have emerged, with and without the contribution of rigid body motion. This paper first describes the previously published phase-field model with an advection term driven by rigid body motion. The model is then used to investigate the differences between models with and without rigid body motion in new benchmark geometries exhibiting markedly different behavior. Sensitivity studies concerning the parameters of the rigid-body motion model are conducted and their effects on equilibrium and kinetic properties explored. In particular, it is shown by simulations that a shrinkage rate independent of system size requires the inclusion of an advection term. Finally, the reason behind this behavior is explored and implications for diffusion-only models are drawn.