Preparation of Yttria with Elongated Grains and Micro-Pores
The effect of 1mol% calcia additive on sintering of yttria was investigated, and a yttria with elongated grains and micro-pores was developed in present work. The results showed that in calcia added samples heated at 1600°C, calcia contained yttria solid solution grains were formed and distributed among pure yttria grains. With the prolonging soaking time, they were concentrated into rod- or plate-like elongated grains and some of them were embedded into pure coarse yttria grains. Furthermore, in calcia added samples, grain growth was much faster and lots of micro-pores were left in coarse pure yttria grains. Water quench test revealed that thermal shock resistance of calcia added sample was greatly improved by elongated grains and micro-pores.
Huaiying Zhou, Tianlong Gu, Daoguo Yang, Zhengyi Jiang, Jianmin Zeng
W. B. Dai et al., "Preparation of Yttria with Elongated Grains and Micro-Pores", Advanced Materials Research, Vols. 197-198, pp. 425-428, 2011