A Phase-Field-Micromechanics Study on the Microstructural Evolution during Viscous Sintering

TL;DR

This paper introduces a phase-field-micromechanics model for simulating viscous sintering, capturing microstructural evolution and physical quantities with validation against analytical and experimental data, aiding process optimization.

Contribution

The study develops a thermodynamically consistent phase-field-micromechanics model to analyze viscous sintering, addressing large deformations and surface evolution challenges in traditional methods.

Findings

Model accurately predicts microstructural evolution.

Validated against analytical solutions and experiments.

Provides insights into stress and strain development.

Abstract

In the manufacturing process of high-performance particulate materials, viscous sintering plays a crucial role, particularly in fields such as polymer processing and additive manufacturing. The interactions between microscopic particles, their flow behavior, and the evolution of porosity during the viscous sintering process directly influence the material's density and mechanical properties. Therefore, developing efficient modeling techniques to simulate the viscous sintering process is essential for optimizing sintering technology. However, the large deformations and dynamic surface evolution inherent in the viscous sintering of particulate materials present challenges to traditional methods based on the sharp interface model. To address these challenges, we propose a thermodynamically consistent diffusion interface model, referred to as the phase-field-micromechanics model, to analyze the evolution of various physical quantities throughout the viscous sintering process. This model implicitly describes the evolution of particle morphology through an introduced phase-field variable. Through comparisons with analytical solutions and experimental data, we rigorously validate the correctness of the proposed model qualitatively and quantitatively under both isothermal and non-isothermal conditions. Using the proposed model, we explore the development of strain and stress during the sintering process, as well as the effects of particle size, shape and arrangement on the overall sintering behavior. The evolution of these characteristic indicators allows for a clear observation of the viscous sintering process, which is vital for understanding the mechanisms behind viscous sintering and for guiding industrial production.