Microstructure characterization of gas-pressure-sintered [beta]-silicon nitride containing [beta]-silicon nitride seeds

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb07277.x· OSTI ID:7303194

Hirosaki, Naoto; Akimune, Yoshio ^[1]; Mitomo, Mamoru ^[2]

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1. Nissan Motor Co., Ltd., Yokosuka (Japan). Nissan Research Center
2. National Inst. for Research in Inorganic Materials, Ibaraki (Japan)

Fine [beta]-Si[sub 3]N[sub 4] powders with or without the addition of 5 wt % of large [beta]-Si[sub 3]N[sub 4] particles (seeds) were gas-pressure sintered at 1,900 C for 4 h using Y[sub 2]O[sub 3] and Al[sub 2]O[sub 3] as sintering aids. The microstructures were examined on polished and plasma-etched surfaces. These materials had a microstructure of in situ composites with similar small matrix grains and different elongated grains. The elongated grains in the materials with seeds had a larger diameter and a smaller aspect ratio than those in the materials without seeds. A core/rim structure was observed in the elongated grains; the core was pure [beta]-Si[sub 3]N[sub 4] and the rim was [beta]SiAlON. These results show that the large [beta]-Si[sub 3]N[sub 4] particles acted as seeds for abnormal grain growth and the rim was formed by precipitation from the liquid containing aluminum.

• OSTI ID: 7303194
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 77:4; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ADDITIVES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
DATA
EXPERIMENTAL DATA
FABRICATION
GRAIN GROWTH
INFORMATION
MICROSTRUCTURE
MORPHOLOGY
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
SILICON COMPOUNDS
SILICON NITRIDES
SINTERING
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES