Hot-Pressing of Silicon Nitride Containing Low Amounts of $Y_2O_3$ and AlN

Y2O3-AlN 미량첨가 질화규소의 열간가압소결

  • 조덕호 (명지대학교 무기재료공학과) ;
  • 이형복 (명지대학교 무기재료공학과)
  • Published : 1992.02.01

Abstract

Partially stabilized alpha-sialon composition (X=0.1) powder was hot-pressed at 1800~200$0^{\circ}C$ for 0~90 min with 30 MPa. Sintering behavior, phase changes and mechanical properties for the specimens were studied. As sintering temperature was raised from 1800 to 190$0^{\circ}C$, the relative density tended to increase and reached 99% of theoretical at 190$0^{\circ}C$. However the amount of alpha-sialon decreased because alpha-sialon transformed to beta-Si3N4 and yttrium rich silicate glass. In the case of hot-pressing at 190$0^{\circ}C$ for various times, densification increased with sintering time and full densification above 99% of theoretical was attained by 30 min. The amount of alpha-sialon decreased with sintering time. The maximum strength of 825 MPa was obtained by hot-pressing at 190$0^{\circ}C$ for 60 min.

Keywords

References

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