Mechanical characteristics of mixed soda-lime silicate glasses

The Vickers hardness number and the crack-formation resistance were determined for soda-lime silicate glasses (SLS) subjected to chemical treatment either in AgNO3+NaNO3 or in a KNO3 bath. The effectiveness of the Na+⇄Ag+ ion exchange process was modified by thermal treatment of the samples. It was found that partial substitution of the mobile Na+ ions either by Ag+ or K+ ions results in a strengthening of the SLS glasses, while the effect of potassium is larger than that induced by silver, although the radius of both ions is nearly the same.