The magazine «Glass and Ceramics» for December 2023 has been published

Dear Colleagues!

Viktor Osipov, President of the Association "StekloSouz" of Russia, is a Member of the Editorial Board of the Glass and Ceramics magazine.

We inform you that the 12th issue of the monthly scientific and technical magazine “Glass and Ceramics” for 2023 has been published.

Contents of the December issue:

✔ TECHNOLOGICAL METHODS FOR INCREASING FLUORINE CONTENT IN GLASSES OF THE SrO–Al2O3–P2O5–SiO2–F SYSTEM FOR GLASS IONOMER CEMENTS

The influence of technological parameters of glass melting in the SrO–Al2O3–P2O5–SiO2–F system on the value of the refractive index of glass and the fluorine content in it was studied. Tableting the charge and lowering the cooking temperature makes it possible to obtain glasses with a high fluorine content - up to 17 wt. %; in this case, the value of the refractive index nD decreases to ~1.49, which significantly improves their aesthetic characteristics and expands the possibilities of using glass ionomer cements as fillers. It was experimentally established that in the studied multicomponent glass with two glass-forming oxides (SiO2 and P2O5) at a high Al2O3 content, each mass percent of fluorine leads to a decrease in the refractive index by ?3.5•10–4.

✔ FACING BUILDING MATERIAL BASED ON GLASS GLASS MODIFIED WITH POTASSIUM HYDROXIDE

A technology for facing material based on mechanically activated cullet modified with potassium hydroxide has been developed. The phase composition, macro- and microstructure of the facing material have been studied. It has been established that the structure of the composite modified with potassium hydroxide is represented in the interpore space by needle-shaped and columnar crystals of potassium silicates. The physical and mechanical characteristics of the facing material have been studied.

✔ INFLUENCE OF ALKALINE COMPONENTS ON THE PROPERTIES OF DENTAL FILLING GLASSES

The effect of modifying the composition of glasses of the strontium aluminoborosilicate (SABS) system on their technological and physicochemical properties has been studied. The introduction of two alkalis into the glass composition made it possible to significantly reduce the melting temperature from 1500 to 1450°C, which led to changes in the properties of the glass.

When introduced into the glass composition up to 5 mol. % alkalis, the coefficient of thermal linear expansion (TCLE) decreased from 58 to 50 (?? 10–7 K–1), and the refractive index nD – from 1.551 to 1.528. However, alkaline components negatively affect the hydrolytic resistance of glass, transferring them from ? V ?? hydrolytic class. The solution to this problem was: 1) the use of a polyalkaline effect, 2) maintaining high radiopacity of glass by introducing a small amount of highly effective radiopaque barium oxide into its composition and a significant reduction in the content of strontium oxide, 3) increasing the content of aluminum oxide, which usually leads to increased chemical resistance glass As a result, an improvement in cooking properties was achieved with a decrease in the cooking temperature and glasses were obtained with high values of X-ray contrast (~550%), light transmittance (T = 90%), refractive index values nD = 1.530 and LTLE = 56 (?? 10–7 K –1) while maintaining chemical resistance to water corresponding to ? hydrolytic class.