☆ 4.7 Article

Densification behavior of a fine-grained MgAl2O4 spinel during spark plasma sintering (SPS)

SCRIPTA MATERIALIA (2010)

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Journal

SCRIPTA MATERIALIA
Volume 63, Issue 6, Pages 565-568

Publisher

PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.scriptamat.2010.06.012

Keywords

Powder consolidation; Spark plasma sintering; Ceramics; Deformation structure

Categories

Nanoscience & Nanotechnology Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering

Funding

  1. Amada Foundation [AF-2008016]
  2. Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan [B:19760497, C:22560675, B:21360328]

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The densification rate of a spinel during spark plasma sintering can be characterized by the decreasing stress exponent from >= 4 to approximate to 1 as the density increases. Transmission electron microscopy observations showed that stacking faults introduced by partial dislocations are observed in a low-density region, but limited in a high-density region. These results suggest that the dominant densification mechanism changes with density, from plastic flow caused by a partial dislocation motion to diffusion creep as the density increases. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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