Fabrication of <TEX>$Al_2O_3/SiC$</TEX> Composite Through Oxidation of SiC

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J. Korean Ceram. Soc. > Volume 34(5); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(5): 535.

SiC의 산화에 의한 $Al_2O_3/SiC$ 복합체의 제조

김경환, 이홍림, 이형민, 홍기곤¹

연세대학교 세라믹공학과
¹포항산업과학연구원

Fabrication of $Al_2O_3/SiC$ Composite Through Oxidation of SiC

ABSTRACT

The surface of SiC particles were partially oxidized to produce SiO2 layers on the SiC particles to prepare Al2O3/SiC composite by formation of mullite bonds between the grains of Al2O3 and SiC during sintering at 1$600^{circ}C$. This process is considered to enable the sintering of Al2O3/SiC composite at lower temperature and also to relieve the stress, produced by thermal expansion mismatch between Al2O3 and SiC. In fact, Al2O3/SiC composite prepared by oxidation of SiC was observed to be more effectively sintered and densified at lower temperature. Maximum density, flexural strength and microhardness were obtained with 5.65 vol% of mullite content in Al2O3/SiC composite.

Key words: $SiO_2$, layer, $Al_2O_3/SiC$ composite, Mullite, Thermal expansion mismatch, Oxidation of SiC