Abstract
A method is proposed for determining proof strength of ceramic components based on fracture behavior. The strength for short time fracture mainly depends on the sizes of initial defects in the ceramics, but it cannot be uniquely determined by the constant fracture toughness criterion which is well known for applicability to brittle materials. For static fatigue behavior, a static fatigue limit below which cracks are arrested is observed. Both short-time fracture strength and static fatigue limit are shown to have nonlinear relationships to defect size. By considering these dependences, the method gives proof strength which is effective in designing ceramic components.
