Microstructure and Fracture Characteristic of Reaction-Sintered <tex>$Si_3N_4$</tex>-TiN Composite

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J. Korean Ceram. Soc. > Volume 33(6); 1996 > Article

Journal of the Korean Ceramic Society 1996;33(6): 686.

반응소결에 의해 제조된 $Si_3N_4$-TiN 복합세라믹스의 미세조직과 파괴특성

이병택, 김해두

한국기계연구원 재료기술연구부 요업재료그룹

Microstructure and Fracture Characteristic of Reaction-Sintered $Si_3N_4$-TiN Composite

ABSTRACT

Relationship between microstructure and fracture characteristic of reaction-sintered Si3N4-TiN composite has been studied by optical microscope X-ray diffractometer scanning electron microscope and transmission electron microscope. Reaction-bonded Si3N4-TiN composite containing many residual pores was constructed with $alpha$-Si3N4 $beta$-Si3N4 and TiN crystallines as well as some amounts of residual Si. By the post-sintering the composite was changed to rod-like Si3N4 grains an dense body contained $beta$-Si3N4 and TiN phases. No resction compounds wee formed at the interfaces between Si3N4 and TiN grains. The main fracture mode was intergranular type. and the fracture toughness was found to be 10.4MPa.m1/2due to the crack deflection crack bridging and microcracking mechanisms

Key words: Cramic composite, Reaction-sintering, $Si_3N_4$-TiN