Effects of Stress Ratio on the Fatigue Strength of Silicon Nitride Balls under Cyclic Pressure Loads

摘要

In our previous works, we found that splitting failures of silicon nitride balls under cyclic pressure loads were caused by pre-cracks initiated on their equators by a Vickers indenter [1]. In the present work, in order to examine the mechanism of the splitting failures, we carried out fatigue tests at different stress ratios and investigated the effect of the stress ratios and the equivalent stress intensity factor on the fatigue strength.