Modeling the microstructural evolution during constrained sintering

TL;DR

This paper introduces a coupled numerical model combining kinetic Monte Carlo and finite element methods to simulate microstructural evolution during constrained sintering, capturing stress effects and resulting anisotropic shrinkage.

Contribution

It presents a novel integrated modeling approach that couples microstructural kinetics with stress analysis for constrained sintering processes.

Findings

Simulation shows increased pore formation near the substrate.

Results reveal anisotropic shrinkage and strain distribution.

Model predictions align with experimental observations.

Abstract

A numerical model able to simulate solid-state constrained sintering is presented. The model couples an existing kinetic Monte Carlo (kMC) model for free sintering with a finite element model (FEM) for calculating stresses on a microstructural level. The microstructural response to the local stress as well as the FEM calculation of the stress field from the microstructural evolution is discussed. The sintering behavior of a sample constrained by a rigid substrate is simulated. The constrained sintering results in a larger number of pores near the substrate, as well as anisotropic sintering shrinkage, with significantly enhanced strain in the central upper part of the sample surface, and minimal strain at the edges near the substrate. All these features have also previously been observed experimentally.