Sintering Atmosphere Effect on the Grain Size and Phase Distribution of a Zirconia

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J. Korean Ceram. Soc. > Volume 36(11); 1999 > Article

Journal of the Korean Ceramic Society 1999;36(11): 1198.

$ZrO_2$ 의 입자크기과 상분포에 미치는 소결분위기 영향

백용균, 안중호

안동대학교 재료공학부

Sintering Atmosphere Effect on the Grain Size and Phase Distribution of a Zirconia

ABSTRACT

The effect of sintering atmosphere on the grain sizes and phase distributions in 3Y-ZrO2 and 8Y-ZrO2 was investigated O2 and N2 were used as sintering atmospheres. In the case of 3Y-ZrO2 the sintered density was higher in N2 than in O2 while in the case of 8Y-ZrO2 contrary results were obtained. The observation can be explained by the nitrogen solubility into the zirconia lattice. That is nitrogen gas can behave as a diffusive gas contrary to the behavior in other oxides depending on the amount of Y2O3. In 3Y-ZrO2 tetragonal phase was retained at room temperature irrespective of sintering atmospheres. Grain sizes of two specimens were below 2㎛ and larger in O2 thin in N2 Under a given stress the transformability of tetragonal phase into monoclinic phase was higher in O2 than N2. The results are discussed on the basis of an effect of the grain size and non-transformable ttragonal(t') phase.

Key words: Zirconia, Sintering, Sintering atmosphere, Grain size, Phase distribution