R-curve effect on strength and reliability of toughened ceramic materials

Abstract

An improved theoretical analysis is presented for the strength and mechanical reliability of ceramic materials with an R-curve characteristic. There is good agreement between the predicted flexural strength distribution of an Al2O3/ZrO2 ceramic and experimental datA. Unlike the conventional two-parameter Weibull approach, this new analysis is able to predict the non-linearity observed in the lnln 1/(1-Pf) versus In σf strength distribution curve. Compared to the untoughened Griffith material, the R-curve material has higher strength and better strength reliability. © 1995 Chapman & Hall.