Paper Titles

Sintering Fundamentals: Historical Aspects
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Sintering Simplified: Surface Area, Density, and Grain Size Relations
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Rheology and Kinetics of Pressure Sintering
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Dilatometry Coupled with Mass Spectrometry as Instrument for Process Control in Sintering of Powder Metallurgy Steels
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Sintering Mechanisms of Functionally Graded Cemented Carbides
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Doped Ceria Based Solid Oxide Fuel Cell Electrolytes and their Sintering Aspects: An Overview
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Sintering and Microstructural Modification of Seeded and Neodymium Doped Lanthanum Hexaaluminate
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HomeMaterials Science ForumMaterials Science Forum Vol. 835Sintering Simplified: Surface Area, Density, and...

Sintering Simplified: Surface Area, Density, and Grain Size Relations

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Abstract:

Sintering involves several interactions as particles bond and enable microstructure evolution toward a minimized energy condition, resulting in a complex interplay of measurement parameters. Overriding the evolution is energy minimization, and from that perspective some simple relations emerge. The natural progression is determined by energy reduction, measured by surface area, density, and grain boundary area (grain size). Contrary to the usual sintering analysis that starts with atomic level mass transport mechanisms, presented here is an approach that links to global energy reduction during sintering to simple monitors. Initially sintering converts surface area into lower energy grain boundary area. Subsequently grain growth annihilates grain boundary area. Thus, grain boundary area peaks at intermediate sintered densities, while surface area continuously declines. The trajectory follows a straightforward dependence on density as illustrated using data for a wide variety of materials and consolidation conditions.

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Sintering Fundamentals II

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Periodical:

Materials Science Forum (Volume 835)

Pages:

50-75

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.835.50

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Online since:

January 2016

Authors:

Randall M. German*

Keywords:

Coarsening, Densification, Density, Distortion, Grain Growth, Grain Size, Gravity, Microstructure, Porosity, Shrinkage, Sintering, Surface Area

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* - Corresponding Author

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