J0405-5-4 Increase in speed of self-crack healing ofAl_2O_3/SiC composite by SiC nano sizing

Abstract

An increase in speed of self-crack healing of Al_2O_3/SiC composite by SiC nano-sizing was attempted. Self-crack healing of ceramics is induced by the high-temperature oxidation of SiC. The surface energy of SiC particles is increased by nano sizing of SiC, and the reaction rate of SiC oxidation increase. Two Al_2O_3/18 vol. % SiC, which average grain sizes composed SiC were 20-150 nm and more less than 10 nm were prepared in the present study. SiC oxidation temperature was measured by differential thermal analysis. Also self-crack healing behavior was investigated. SiC nano sizing was found to be able to accelerate the reaction rate of SiC oxidation. It was, however, found that excess SiC nano sizing made disadvantage to heal the introduced crack completely at any temperature.