Cyclic fatigue life of SiAlON at room temperature

The fatigue life of a SiAlON material was evaluated at room temperature in a rotating beam tester. No significant effect of stress level was determined. Failure origins were associated with processing and powder impurities, and consisted primarily of porosity and inclusions in the bulk material. The experimental design was such that a sufficient number of failures at each stress level would produce a good estimate of the distribution, and a test of the influence of a high stress level on fatigue life could be achieved.