Measurements of indentation crack length vs applied bend stress mere u
sed to develop a new method of analysis for determining short-crack to
ughness curves. Three glass-ceramics and a polycrystalline alumina wer
e used as prototype test materials. Crack-shape effects mere incorpora
ted into the analysis. The magnitude of the residual-stress factor can
be determined independently from the experimental data using the meth
odology. In contrast to other test methods using indentation precracks
, calibration constants or reference materials are not required for ob
taining absolute values of the toughness, Good agreement with conventi
onal toughness values reported for the long-crack limit mas obtained f
or the different materials tested.