Glass for glass metal seals - comprises silica, phosphorus pent:oxide, alkali(ne earth) oxide(s), transition metal oxide(s) and opt. fluoride

摘要

Glass for glass metal seals with good adhesion to steel and alloys of the Cr/Fe type comprises by wt. 40-70% SiO2, 0-20% B2O3, 1-15% P2O5, 0-10% Al2O3, 0-15% TiO2, 0-10% Li2O + Na2O + K2O, (0-2% Li2O), 0-20% MgO+SrO+BaO+CaO, (0-5% MgO) 0-5% PbO, 0-2% ZnO, 0.3-3% CoO, 0-3% NiO, 0-5% MnO, 0-3% Fe2O3, 0-1% Cr2O3, 0-1% Cu2O, 0-4% F. The glass has a coefft. of expansion of 9.10-6/degrees K in the range 20-300 degrees C. The glass is used for sealing electric leads inside metal housings through the wall of the housing to electrical and electonic devices inside the housing. The claimed compsn. provides better adhesion to the steel than in prior art, because of its P2O5 content.