Properties of the $\beta$-SiC+39vol.%$ZrB_2$ Composites with $Al_2O_3+Y_2O_3$ additives

$Al_2O_3+Y_2O_3$를 첨가한 $\beta$-SiC+39vol.%$ZrB_2$ 복합체의 특성

  • Shin, Yong-Deok (School of Electrical and Electronic, WonkWang Univ.) ;
  • Ju, Jin-Young (School of Electrical and Electronic, WonkWang Univ.) ;
  • Jin, Hong-Bum (Division of Electrical Materials applied Superconductive Lab., KERI) ;
  • Park, Gi-Yub (Group dep. of Electrical and Electronics, PuSan College of Information Technology) ;
  • Yea, Dong-Hun (Pennstate Univ. MRL)
  • 신용덕 (원광대학교 공과대학 전기전자공학부) ;
  • 주진영 (원광대학교 공과대학 전기전자공학부) ;
  • 진홍범 (한국전기연구소 초전도 연구실) ;
  • 박기엽 (부산정보대학 전기전자계열) ;
  • 여동훈
  • Published : 1999.07.19

Abstract

The ${\beta}-SiC+ZrB_2$ ceramic composites were hot-press sintered and annealed by adding 1, 2, 3wt% $Al_2O_3+Y_2O_3$(6 : 4wt%) powder as a liquid forming additives at $1950^{\circ}C$ for 4h. In this microstructures, no reactions were observed between $\beta$-SiC and $ZrB_2$, and the relative density is over 90.79% of the theoretical density and the porosity decreased with increasing $Al_2O_3+Y_2O_3$ contents. Phase analysis of the composites by XRD revealed of $\alpha$-SiC(6H, 4H), $ZrB_2$, $Al_2O_3$ and $\beta$-SiC(15R). Flexural strength showed the highest of 315.46MPa for composites added with 3wt% $Al_2O_3+Y_2O_3$ additives at room temperature. Owing to crack deflection and crack bridging of fracture toughness mechanism, the fracture toughness showed the highest of $5.5328MPa{\cdot}m^{1/2}$ for composites added with 2wt% $Al_2O_3+Y_2O_3$ additives at room temperature.

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