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Erschienen in: Journal of Materials Science 8/2018

04.12.2017 | Interface Behavior

Implementation of a phase field model for simulating evolution of two powder particles representing microstructural changes during sintering

verfasst von: Sudipta Biswas, Daniel Schwen, Vikas Tomar

Erschienen in: Journal of Materials Science | Ausgabe 8/2018

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Abstract

In this work, we present a multiphysics phase field model for capturing microstructural evolution during solid-state sintering processes. The model incorporates modifications of phase field equations to include rigid-body motion, elastic deformation, and heat conduction. The model correctly predicts consolidation of powder particles during sintering because of two competing mechanisms—neck formation and grain growth. The simulations show that the material undergoes three distinctive stages during the sintering process—stage I where neck or grain boundary between two particles is formed, stage II in which neck length stabilizes and growth or shrinkage of individual particles initiates, and finally stage III with rapid grain growth leading to disappearance of one of the grains. The driving forces corresponding to different mechanisms are found to be dependent on the radius of the particles, curvature at the neck location, surface energy, and grain boundary energy. In addition, variation in temperature is found to significantly influence the microstructure evolution by affecting the diffusivity and grain boundary mobility of the sintered material. The model is also used to compare sintering simulation results in 2D and 3D. It is observed that due to higher curvature in 3D, model predicts faster microstructural evolution in 3D when compared to 2D simulations under identical boundary conditions.

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Metadaten
Titel
Implementation of a phase field model for simulating evolution of two powder particles representing microstructural changes during sintering
verfasst von
Sudipta Biswas
Daniel Schwen
Vikas Tomar
Publikationsdatum
04.12.2017
Verlag
Springer US
Erschienen in
Journal of Materials Science / Ausgabe 8/2018
Print ISSN: 0022-2461
Elektronische ISSN: 1573-4803
DOI
https://doi.org/10.1007/s10853-017-1846-3

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