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PUBLICATIONS

Blunt scratch strength of polycrystalline alumina

Published

Author(s)

Robert F. Cook

Abstract

A model for the fracture strength of brittle materials controlled by blunt (spherical) scratches is developed and compared with measurements on a polycrystalline alumina. The model is based on a residual stress-intensity factor for median cracks at scratches that include a localized plastic deformation zone formed by dragged spherical contacts. The stress-intensity factor depends non-linearly on the normal contact load, P, resulting in a predicted strength variation of P<-3/4>. The strength result validates previous claims and extends the overall indentation-strength framework. However, the result has only limited effectiveness in describing experimental measurements, pertaining only to ideal blunt scratches formed over a limited load domain.
Citation
Journal of the American Ceramic Society
Pub Type
Journals

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Keywords

alumina, fracture, indentation, mechanical properties, scratch
Ceramics

Citation

Cook, R. (2017), Blunt scratch strength of polycrystalline alumina, Journal of the American Ceramic Society, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923796 (Accessed October 12, 2025)

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Created August 21, 2017, Updated September 29, 2025
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