GLASS FOR GLASS CERAMIC CEMENT Russian patent published in 2002 - IPC

FIELD: glass industry. SUBSTANCE: invention relates to glass for glass ceramic cement used in instrument making and radioelectronics industry for soldered joint with langacite (La₂Ga₅SiO₁₄) in production of high-temperature resonators. Glass comprises components taken in the following ratio, wt. %: SiO₂, 30.5-35.5; B₂O₃, 6.5-7.5; Al₂O₃, 7.0-8.0; BaO, 28.5-30.5; ZnO, 20.5-22.0; MgO, 0.5-1.5; CdO, 0.5-1.5. Temperature coefficient of linear expansion of glass ceramic cement = 50 x 10^-7K^-1; crystallization and soldering point is 820-850 C; deformation point is 1050 C. EFFECT: improved properties and indices of glass ceramic cement. 1 tbl