TRANSPARENT LITHIUM GLASS-CERAMIC MATERIAL, PRODUCTION AND USE THEREOF

摘要

A lithium-containing, transparent glass-ceramic material is provided. The material has low thermal expansion and has an amorphous, lithium-depleted, vitreous surface zone. The zone is at least 50 nm thick on all sides and encloses a crystalline interior, which has high transmission. The material includes a transition region connecting the zone and the interior.

主权项

1. A method for producing a glass-ceramic material, comprising:
supporting a starting glass containing nucleating agents in a kiln a support plate, the support plate having a contact side in contact with the starting glass including at least one supply/removal line; inducing a defined air moisture content in the kiln via the at least one supply/removal line; subjecting the starting glass to a nucleation temperature in the range from 700 to 810° C. for a residence time between 3 and 120 minutes to form glass with nuclei; heating the glass with nuclei from the nucleation temperature to a first ceramicization temperature of 810 to 880° C. at a heating rate of 0.1 to 5.0 K/min to form at least partially ceramicized glass; heating the at least partially ceramicized glass from the first ceramicization temperature to a second ceramicization temperature of 880 and 970° C. and holding at the second ceramicization temperature, after heating, for between 1 and 45 minutes to form the glass-ceramic material; and cooling the glass-ceramic material from the second ceramicization temperature to below 600° C. at a cooling rate of at least 5 K/minute.