| 摘要 |
This invention relates to processes for preparing a ceramic article having as its principal crystalline phase a leucite/pollucite solid solution. The process involves the use of a zeolite to form the article. Zeolites which can be used are those that have a SiO2/Al2O3 ratio of about 3.5 to about 7.5 such as zeolite Y. The zeolite is exchanged with potassium, rubidium and cesium, then calcined at a temperature of about 900 DEG to about 1100 DEG C. for a time to collapse the zeolite framework and provide an amorphous powder. Next, the amorphous powder is formed into a shaped article and the article is sintered at a temperature of about 1150 DEG to about 1400 DEG C. for a time of about 0.5 to about 12 hours to give a ceramic article whose principal crystalline phase is a leucite/pollucite solid solution, is substantially crack free, has less than 5% porosity, and a coefficient of thermal expansion of about 2x10-6 to about 27x10-60C-1. This invention also relates to the leucite/pollucite ceramic article.
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