OS0803 ショットピーニングと自己き裂治癒を応用したセラミックスの信頼性向上(ガスタービン材料の各種力学特性,オーガナイズドセッション)

抄録

This study aimed to establish a new method for improving the strength and reliability of the ceramics, which combined the crack healing ability with shot peening. Si3N4/SiC composite ceramics having high crack healing ability was used. To evaluate the effect of shot peening, the distribution of the residual stress and mechanical strength property of shot peened specimens were investigated. Moreover, the utility of shot peening effects on the crack healing ability was also investigated. The main conclusions were as followed; (1) Shot peening induced effective compressive residual stress on the ceramics. (2) The fracture toughness on the surface was improved by factor of 2.3 - 2.5. (3)The bending strength of pre-cracked specimens recovered due to shot peening and crack-healing. (4) The contact strength was dramatically improved by shot peening. (5) The best heat-treated temperature on the combined method was 800 - 1100℃.