S042011 SiCウイスカー強化Si_3N_4複合セラミックスの亀裂治癒現象について([S04201]セラミックスおよびセラミックス系複合材料(1))

抄録

SiC whisker reinforced Si_3N_4 composite was used for studying crack healing behavior. The semi-elliptical surface cracks with the length of 200μm, 600μm, 3mm were introduced on the specimens using Vickers hardness indenter. The cracked specimens were heat-treated at 1000℃, 1100℃, 1200℃ and 1300℃ for 1 hour in air. Bending strength was measured at room temperature in air by three point bending test system. Bending strength of cracked specimen reduced to about 50% of that of smooth specimen. However, bending strength of some pre-cracked and heat treated specimens recovered completely up to that of smooth specimen.