| 摘要 |
A glass for sealing a beta- alumina tube in a sodium-sulphur cell has a composition suitable to resist attack by sodium at elevated temperatures and a coefficient of thermal expansion suitable for use with beta-alumina. The glass consists essentially of 28-48 mol % B2O3, 0-20 mol % SiO2, 16-28 mol % Al2O3, together with 18-33 mol % of at least one alkaline earth metal oxide selected from BaO, SrO, CaO and MgO, the proportions of the constituents being such that the combined total of B2O3 and SiO2 is 40 to 60 mol % and furthermore being such that 0.517 A1 + 0.0354 A2 - 0.0063 A3 + 0.168 A4 + 0.1336 A5 + 0.098 A6 + 0.1597 A7, lies between 5.7 and 6.4 where A1, A2, A3, A4, A5, A6 and A7 are the respective molar percentages of B2O3, SiO2 Al2O3, BaO, CaO, MgO and SrO. A cell sealed with such a glass is described. |
