Effect of rare-earth oxides on thermal behavior of alumina-silica glass sealants

Abstract

Thermal behavior of (62.92SiO2-4.71Al2O3-14.83Na2O-5ZrO2-12.54SrO) - 5Re2O3 (Re = Y, La, Nd, Sm) glasses with superstoichiometric additives of rare-earth oxides has been investigated by scanning differential calorimetry, high temperature optical microscopy, and dilatometry. It is found out that an increase in characteristic temperatures (glass transition temperature and temperature of half-sphere formation) is caused by decreasing the ionic radius. The value of thermal expansion coefficient changes insignificantly.