| 摘要 |
A substantially crystalline cordierite ceramic article which is especially suited for electronic applications is formed by taking a shaped article which has been formed either from a magnesium exchanged zeolite powder or from a calcined product thereof, the zeolite selected from the group consistig of phillipsite, harmotome, gismondine, zeolite B, zeolite ZK-19 and zeolite W, and sintering theshaped article at a temperature of about 1,000.degree.C to 1,350.degree.C for about 1 to about 6 hours. The magnesium exchanged zeolite has a SiO2/Al2O3 ratio of about 2.3 to about 2.8 and a sodium content less than 0.5 weight percent. The ceramic articlethat is formed has a substantially crystalline cordierite phase and has a density of at least 90% of its theoretical density. A preferred process involves calcining themagnesium exchanged zeolite powder at a temperature of about 600-800.degree.C tocollapse the zeolite framework and give upon sintering a cordierite ceramic article which is substantially crack free. A preferred magnesium exchanged zeolite is magnesium exchanged zeolite B.
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