| 摘要 |
1479858 Glass-ceramic CARL-ZEISSSTIFTUNG [trading as JENAER GLASWERK SCHOTT & GEN] 20 June 1975 [20 June 1974] 21023/75 Heading ClM A crystallizable glass consists of, in weight per cent: The glass may be converted to a (dark red) transparent glass-ceramic having a crystal phase content not more than 50% by weight, the crystal phase bening h-quartz solid solution and/or h-spodumene, and a heat stress factor more than 1000, by heating at 800-900‹ C. In a preferred embodiment, batch materials for the glass are melted at about 1620‹ C., the melt cooled to about 1480‹ C. and shaped, the shaped glass cooled to below 700‹ C., and the glass crystallized by heating to 800-900‹ C. The crystallization stage, which may be repeated (e.g. 5 times), preferably comprises heating from room temperature to 800‹ C at 1-10‹ C./min., heating from 800‹ to 890‹ C. at about 0.50 C./min, cooling from 890‹ C. to 750‹ C. at 1-7‹ C./min., and cooling from 750‹ C. to room temperature at 1-200‹ C./min. |
