The effect of substitution of Bi_2O_3 for alkali oxides on thermal properties, structure and wetting behavior of the borosilicate glass

摘要

The effect of substitution of Bi_2O_3 for alkali oxides in the borosilicate sealing glass on thermal properties, structure and wetting behavior of the borosilicate glass was studied. The thermal expansion coefficient (TEC) decreased with the substitution, however, the TEC varied little while the alkali oxides were completely consumed. The variation in glass transition temperature (T_g) and the FT1R results of the glasses indicated significant effect of Bi_2O_3 substitution on the glass structure, which caused a progressive conversion of BO_3 to BO_4 unit in the glass. The appropriate amount of Bi_2O_3 obviously improved the wetting performance of the borosilicate glass on Al_2O_3 substrate due to the high polarizability of Bi~(3+) ion.