Fracture resistance behavior of silicon carbide whisker-reinforced alumina composites with different porosities

Journal Article · Thu Mar 01 04:00:00 EST 1990 · Journal of the American Ceramic Society; (USA)

DOI:https://doi.org/10.1111/j.1151-2916.1990.tb06553.x· OSTI ID:6617206

Krause, R F; Fuller, E R ^[1]; Rhodes, J F ^[2]

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1. National Inst. of Standards and Technology, Gaithersburg, MD (USA)
2. Advanced Composite Materials Corp., Greer, SC (US)

Fracture resistance behavior was characterized for SiC-whisker-reinforced alumina composites with porosities ranging from 0.6% to 11.5%. The composites were hot-pressed from an Al{sub 2}O{sub 3} powder with 25 wt% SiC whiskers. Strengths of individual specimens were measured in four-point flexure either for natural flaws or for Vickers-indentation flaws as a function of radial crack size. Indentation crack sizes were controlled with indentation loads which varied between 2 and 200 N. A method of analysis of these measurements indicates that the fracture resistance of these composites increases as a function of crack extension, a rising {ital R} curve. This behavior is interpreted in terms of tractions from both crack-bridging whiskers and interlocking grains, which develop in the wake of the crack tip as it extends.

• OSTI ID: 6617206
• Journal Information: Journal of the American Ceramic Society; (USA), Journal Name: Journal of the American Ceramic Society; (USA) Vol. 73:3; ISSN JACTA; ISSN 0002-7820
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
360603 -- Materials-- Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CARBIDES
CARBON COMPOUNDS
CHALCOGENIDES
CRACK PROPAGATION
CRYSTALS
DATA ANALYSIS
FABRICATION
FRACTURE PROPERTIES
HOT PRESSING
MATERIALS
MATERIALS WORKING
MECHANICAL PROPERTIES
MONOCRYSTALS
OXIDES
OXYGEN COMPOUNDS
POROSITY
POWDERS
PRESSING
REINFORCED MATERIALS
SILICON CARBIDES
SILICON COMPOUNDS
WHISKERS