Study On Chemical Strengthening Of High Aluminosilicate Glass

Aluminosilicate glass has excellent mechanical properties, optical properties and chemical toughened properties. After ion exchange, aluminosilicate glass has a remarkble enhancement effect, and even remains high machinery strength in the case of thinning, which makes aluminosilicate glass a hot study subject in the frontier displines.Three common commercially available aluminosilicate flate glasses (Corning,Schott, Dragontrail) with different aluminum contents were used in this paper. They were treated below glass transition temperature (Tg) by the method of ion exchange.The surface compressive stress (CS), depth of stress layer (DOL) and microhardness(HV) were tested to study the relationship of strengthening conditions and properties.Microhardness and depth of stress layer were mproved as strengthening time extend or strengthening temperature rises. The relationship of surface compressive stress and strengthening conditions was not clear. The depth of stress layer has greater influence on microhardness than The surface compressive stress.Activation energy and interdiffusion coefficient were calculated based on the depth of stress layer. Based on the calculation results and other researchers' research production, we found that the interdiffusion coefficient is almost constant. The interdiffusion coefficients of 395?, 400?, 405?, 410? were 3.742×10-10 cm2/s?4.641 ×10-10 cm2/s?5.338×10-10cm2/s?5.416×10-10 cm2/s, respectively. The activation energy of Corning glasses was 110.9KJ/mol and 122.691 KJ/mol based on two different computing methods.The impact of strengthening conditions on structure of glasses was studied with micro-Raman spectrum. The results shows that: As the amount of exchanging ion increases,the intensity of the peak at ca.?980 cm-1 and the peak at ca.?1140 cm-1 decreases relative to the peak at ca. -1075cm-1. The intensity of the peak at ca. ?490 cm-1 and the peak at ca.?560cm-1 increases. The reason is that: by redistributing locally the negative charge from Q2 and Q4 to Q2 units, the amount of bridge oxygen which cound be used to form rings increases.