Tribological characteristics of Si[sub 3]N[sub 4] ceramic in high-temperature and high-pressure water

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

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb07032.x· OSTI ID:7207472

Kitaoka, Satoshi; Tsuji, Toshihide; Katoh, Toshio ^[1]; Yamaguchi, Yoshimi; Sato, Koji ^[2]

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1. Nagoya Univ. (Japan). Dept. of Nuclear Engineering
2. Japan Fine Ceramics Center, Nagoya (Japan). Research and Development Lab.

The effects of sliding speed and dissolved oxygen on the tribological behavior of Si[sub 3]N[sub 4] sliding on itself in water were investigated to room temperature and at 120 C saturated vapor pressure. The friction coefficients and specific wear rates at 120 C were much larger than those at room temperature and had a minimum at about 0.4 m/s, whereas the specific wear rate of the disk increased with increasing the sliding speed. The wear rate at lower sliding speeds in water at 120 C is considered to be primarily controlled by the increase of the contact stress on the asperities which are formed by the dissolution of grain boundaries of the Si[sub 3]N[sub 4] ceramic and the subsequent dissolution of the silica layer of the reaction products. However, the wear rate at higher sliding speeds is governed by the direct oxidation and microfracture of the Si[sub 3]N[sub 4] substrate. The tribochemical reaction to product NH[sub 3] mainly occurred at all sliding conditions in water at room temperature and 120 C, and the reaction to produce H[sub 2] gas appeared slightly only at the slidings speeds above 0.4 m/s at 120 C. The tribological behavior was independent of dissolved oxygen concentration for all sliding conditions in water at room temperature and 120 C.

• OSTI ID: 7207472
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 77:2; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
360205 -- Ceramics
Cermets
& Refractories-- Corrosion & Erosion
CHEMICAL REACTIONS
FRICTION
GRAIN BOUNDARIES
MICROSTRUCTURE
NITRIDES
NITROGEN COMPOUNDS
OXIDATION
PNICTIDES
SILICON COMPOUNDS
SILICON NITRIDES
SLIDING FRICTION
WEAR