Temperature Dependence of Glass Microhardness

A method is proposed for calculating the temperature dependence of the microhardness of glass in the temperature range from absolute zero to the glass transition temperature. According to the model underlying the calculation, the glass passes into a plastic state not only under the action of temperature but also under the action of mechanical stresses above the critical value corresponding to microhardness. Therefore, under the simultaneous action of these two factors, the glass passes into a plastic state if the sum of the thermal and mechanical energy of the glass mesh exceeds the critical value. The proposed calculation method is tested on the example of organic glass and two of the most important oxide glasses for practice: fused quartz and industrial alkali-silicate glass (soda-lime-silica glass (SLSG).