Indentation toughness of ceramics: a statistical analysis

Direct indentation method was employed to measure the toughnesses for soda-lime glass and a TiC particulate reinforced Al2O3 composite. The statistical aspect of the resultant indentation toughness was then analyzed. It was found that the indentation toughness measured at a given indentation load for a given material exhibits a large scatter and can be described with a two-parameter Weibull distribution function. Analyses based on the observations of the crack/microstructure interactions showed that the statistical variability in the measured indentation toughness may be attributed to the effect of microstructural inhomogeneity on the local crack resistance.