A new theory was formulated for analyzing the cyclic fatigue behavior of ceramics by combining the multi-modal Weibull distribution function with slow crack growth law (S. C. G.). Using an internal pressure testing machine, static and fatigue tests were performed on cylindrical alumina specimens. Statistical data analysis showed that cyclic stress reduces the number of cycles to failure. Intergranular fracture was dominant on fatigue fractured surfaces. The semi-length of the crack at branching has been best correlated with the peak applied stress in the cyclic fatigue test. The least of the number of cycles to failure was ensured for the specimens passing through the pre-loading proof test.
