On the local crack resistance of Al2O3–TiC composites evaluated by direct indentation method

Vickers indentation tests were conducted on an Al2O3–TiC composite at different load levels. The crack resistance calculated from the length of the indentation-induced crack exhibits a large scatter. Such a large scatter can be characterized well with Weibull statistics and can be attributed to the effect of microstructural inhomogeneity on the local crack resistance. The effect of the statistical variability in the measured crack resistance on R-curve evaluation was also discussed and the direct indentation method was suggested to be the most suitable method for the evaluation of the R-curve behavior for ceramics.