Cyclic Contact Fatigue of Brittle Ceramics

Published

May 10, 1999

Author(s)

Brian R. Lawn, Yeon-Gil G. Jung, D H. Kim, S K. Lee, I M. Peterson

Abstract

Contact damage modes in cyclic loading with spheres are investigated in several ceramics, principally silicon nitride but also some ceramics used for dental restorations. Initial damage to small numbers of cycles and low loads consists of tensile-driven macroscopic cone cracks (brittle mode). Secondary damage at large numbers of cycles and high loads consists of shear-driven distributed microdamage (quasi-Plastic mode), with attendant radial cracks and a new form of deeply penetrating subsidiary cone cracks. Strength tests on indented specimens are used to quantify the degree of damage. Both damage modes degrade the strength: the first, immediately after cone crack initiation, relatively slowly; the second, after development of radial cracks, much more rapidly. Comparison with static contact data indicates a strong mechanical (as opposed to chemical) component in the cyclic fatigue in the quasi-plastic region. The basis for setting up fracture mechanics models is briefly discussed.

Proceedings Title

Fatigue 99 : Proceedings of the International Conference on Fatigue and Fatigue Thresholds

Volume

1

Conference Dates

June 1, 1999

Conference Location

Beijing, CH

Conference Title

International Conference on Fatigue and Fatigue Thresholds

Pub Type

Conferences

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Local Download

Keywords

brittle ceramics, cone cracks, contact fatigue, quasi-plasticity, radial cracks

Citation

Lawn, B. , Jung, Y. , Kim, D. , Lee, S. and Peterson, I. (1999), Cyclic Contact Fatigue of Brittle Ceramics, Fatigue 99 : Proceedings of the International Conference on Fatigue and Fatigue Thresholds, Beijing, CH, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=850017 (Accessed October 31, 2024)