| 摘要 |
THE PROCESS FOR PRODUCING A CHEMICALLY PRESTRESSED GLASS OF VERY HIGH SURFACE QUALITY INCLUDES SUBJECTING AN LI2O-FREE STARTING GLASS FROM THE SIO2-A12O3-M2O-MO SYSTEM WHICH ALSO CONTAINS TIO2, CEO2 AND F2 TO CHEMICAL ION EXCHANGE BY IMMERSING IT IN A POTASSIUM SALT BATH AT A TEMPERATURE BETWEEN 350°C AND 550°C AND AT A RESIDENCE TIME OF BETWEEN 0.5 AND 20 HOURS TO FORM THE CHEMICALLY PRESTRESSED GLASS. IN A PREFERRED EMBODIMENT OF THE PROCESS, THE POTASSIUM SALT BATH CONTAINS A POTASSIUM NITRATE MELT AND THE GLASS IS POLISHED AFTER PRESTRESSING. THE CHEMICALLY PRESTRESSED GLASS IS PARTICULARLY USEFUL FOR MAKING HARD DISKS.
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