| Autor: |
Li, Junguo, Peng, Aiyi, He, Yong, Yuan, Huiping, Guo, Qilong, Shen, Qiang, Zhang, Liangmeng, Zaykoski, J. |
| Zdroj: |
Journal of the American Ceramic Society; Jul2012, Vol. 95 Issue 7, p2127-2129, 3p |
| Abstrakt: |
Pure YB4 powder was synthesized via the reaction of Y2 O3 with B4 C under a vacuum pressure within the range of 20-50 Pa using spark plasma sintering ( SPS) route. The effect of temperature and the molar ratio of the starting materials was studied. The role of the YBO3, an intermediate product, in the synthesis of YB4 was investigated. For preparation of high purity YB4, the molar proportion of B4 C to Y2 O3 should not be higher than the stoichiometric ratio (15/7). YBO3 can be removed through decomposing to Y2 O3 and B2 O3 or reacting with B4 C to form YB4 and B2 O3 at a temperature above 1650°C. The little residual impurities, such as Y2 O3 and YBO3, can be removed by hydrochloric acid washing. Thus, a high purity YB4 powder has been synthesized. The oxygen content of the obtained YB4 is about 0.007% and the particle size is in the range of 3-10 μm. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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