Improvement of strength and reliability of ceramics by shot peening and crack-healing

In this study we propose a new method for improving the surface strength and reliability of ceramics that combines shot peening with crack-healing ability. We used Si3N4/SiC composite ceramics with high crack-healing ability and subjected the specimens to shot peening and crack healing. To evaluate the effect of our method, we investigated the residual stress after shot peening and crack healing and examined the specimens’ mechanical properties, including apparent fracture resistance, contact strength and bending strength. We found that shot peening and crack healing is effective to increase apparent fracture resistance, contact strength and bending strength