The Effect of Two-dimensional Compressive Stress on the Dissolution Rate of Glass in Water

Abstract

The dissolution behavior of silicate glasses was studied as a function of compressive stress and time. The two-dimensional compressive stress on glass surface was introduced by utilizing the difference of thermal expansion coefficients between glass and ceramic substrate. The release rates of Na+ ions from these glasses into distilled water were determined by using atomic absorption analysis. As a result, the release rates of Na+ ions increased along with an increase of compressive stress in both diffusion and reaction stage, that is contrary to the general concept that compressive stress reduces the diffusion rate because of a decrease in void volume. In order to explain this behavior, the new hydrolysis mechanism under compressive stress was suggested. FTIR measurements were also carried out to support this mechanism.