A frictional-wear mechanism for fatigue-crack growth in grain bridging ceramics

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(93)90145-I· OSTI ID:6301381

Dauskardt, R H ^[1]

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1. Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering

A frictional-wear mechanism to account for cyclic fatigue degradation in polycrystalline ceramics exhibiting grain bridging as the principal toughening mechanism is contemplated. The mechanism is based on repetitive sliding wear degradation of frictional grain bridges which reduces the toughening capacity from bridging under cyclic loads. A micromechanical model is developed to relate the reduction in the frictional pullout stress of bridging grains to material removed by wear processes at the grain/matrix interface. The model provides an insight into the effects of salient mechanical and microstructural variables such as wear rate at the grain/matrix interface, initial residual stress of bridging grains, and the grain size, on fatigue-crack growth behavior. Results of the analysis are compared to experimentally observed fatigue-crack growth rates in coarse grained alumina and silicon nitride and implications of the predicted crack-growth behavior discussed.

• OSTI ID: 6301381
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 41:9; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CARBIDES
CARBON COMPOUNDS
CERAMICS
CHALCOGENIDES
CRACK PROPAGATION
DATA
EXPERIMENTAL DATA
FATIGUE
FRACTURE PROPERTIES
INFORMATION
MECHANICAL PROPERTIES
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
SILICON CARBIDES
SILICON COMPOUNDS
SILICON NITRIDES
STRESS INTENSITY FACTORS
THEORETICAL DATA
TRANSITION ELEMENT COMPOUNDS
WEAR
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES