Ion-exchange temperature matching technology in GRIN glass containing silver ion

Abstract

For making Gradient index (GRIN) glass with silver ion, it is difficult to get glass with high silver content by normal glass moltening process because silver ion will be extruded from molten glass at the high temperature. For solving this hard problem, the two-step ion-exchange process based on sodium rich glass is applied to get GRIN glass containing silver ion. In this process, the matching between the temperature of glass soft point and the highest working point of silver molten salt is one of key technologies. In this paper, the sodium-rich glass was made as the glass substrate for silver ion-exchange. Then the glass composition was adjusted to get transparent sodium-rich glass with low soft point and high chemical stability. On the other hand, the silver salt with high dissociation temperature for ion exchange was studied. At last the glass substrate with low soft point and the salt source with high dissociation temperature were matched at the suitable temperature in order to improve ion-exchange process.