Brittle Fracture Versus Quasi Plasticity in Ceramics: A Simple Predictive Index

Published

March 1, 2001

Author(s)

Y W. Rhee, H W. Kim, Y N. Deng, Brian R. Lawn

Abstract

Simple relations for the onset of competing brittle and quasi plastic damage modes in Hertzian contact are presented. The formulations are expressed in terms of well-documented material parameters, elastic modulus, toughness and hardness, enabling a priori predictions for given ceramics and indenter radii. Data from a range of selected ceramic (and other) materials are used to demonstrate the applicability of the critical load relations, and to evaluate coefficients in these relations. The results confirm that quasi plasticity is highly competitive with fracture in ceramics, over a sphere radius range 1 mm to 10 mm. Implications concerning the brittleness of ceramics in the context of indentation size effects are discussed.

Citation

Journal of the American Ceramic Society

Volume

84

Issue

No. 3

Pub Type

Journals

Keywords

brittle fracture, cone crack, elastic modulus, hardness, Hertzian contact, quasiplasticity, toughness

Citation

Rhee, Y. , Kim, H. , Deng, Y. and Lawn, B. (2001), Brittle Fracture Versus Quasi Plasticity in Ceramics: A Simple Predictive Index, Journal of the American Ceramic Society (Accessed October 20, 2025)