ACID DURABILITY OF SODIUM AND POTASSIUM GALLIOSILICATE GLASSES

The relative chemical durability in nitric acid of three series of glasses in the (Na,K)//2O-Ga//2O//3-SiO//2 system have been studied. In these compositions, gallium is proposed to behave as either a network modifier or former depending on the gallium to alkali ion ratio of the glass. The mechanisms of acid attack as found in the present work are postulated to be a combination of ion exchange and network dissolution dependent upon the glass composition/structure. This results in complex trends in the acid dissolution of these glasses as functions of the gallium to alkali ion ratio, and silica content.