Effects of Crack Propagation and Coalescence on Fatigue Behavior of Glass Ceramics

Examination for Two-Collinear Cracks

Abstract

The effects of interaction and coalescence of cracks on the fatigue behavior of high brittle materials such as glass and ceramics are examined. For glass ceramics specimens with two different center distance collinear cracks introduced by Vickers microhardness indentation, the cyclic fatigue tests were carried out under four point bending load. It was found that the time to failure for a certain applied stress significantly decreased with increasing the number of indentation cracks and the center distance of indentation cracks. The prediction of time to failure with crack interaction and crack coalescence was also carried out. The results were in good agreement with the experimental results. The validity of the proposed method of fatigue life prediction was confirmed.