Microstructural Development of <TEX>$Si_3N_4$</TEX> Ceramics Containing Aligned <TEX>${eta}-Si_3N_4$</TEX> Whisker Seeds

J. Ocean Eng. Technol. 2009;23(5):32-38.

Microstructural Development of $Si_3N_4$ Ceramics Containing Aligned ${eta}-Si_3N_4$ Whisker Seeds

Bae Byoung-Chan,Park Dong-Soo,Seo Won-Chan,Bang Kook-Soo,Park Chan

Division of Advanced Materials Science and Engineering Pukyong National University,Functional Ceramic Materials Group Korea Institute of Machinery and Materials,Division of Advanced Materials Science and Engineering Pukyong National University,Division

배향된 질화규소 휘스커 종자를 함유한 질화규소 세라믹스의 미세구조에 관한 연구

배병찬,박동수,서원찬,방국수,박찬

부경대학교 신소재공학부,한국기계연구원 기능세라믹스그룹,부경대학교 신소재공학부,부경대학교 신소재공학부,부경대학교 신소재공학부

Keywords: Sintering additives, Tape casting, Silicon nitride, Microstructural development, Whisker seeds

핵심용어: 소결조제, 테이프캐스팅, 질화규소, 미세구조 발달, 휘스커 종자

Abstract

Silicon nitride samples with aligned whisker seeds were prepared with different amounts of yttria and alumina as the sintering additives. Their sintering behaviors and the microstructural developments between $1850^{circ}C$ and $2050^{circ}C$ were examined. The sample with larger amount of the sintering additives showed faster densification and grain growth. Even though addition of the aligned whisker seeds slightly retarded densification of silicon nitride, it improved the flexural strength and the fracture toughness. Both the flexural strength and the fracture toughness of silicon nitride with the aligned whisker seeds were increased as the amount of the sintering additives was increased.