Abstract
In the composite materials made from metal and glass, high adhesion between them is required. It was reported that high adhesion obtained by the reaction between metal and glass. The glass composition with high activity coefficient of NiO, which is used as an adhesion agent, is desirable to promote the reaction between them. In order to research an optimum composition of glass with high adhesion to metal, activity coefficients of NiO in borosilicate melts was measured by chemical equilibration method. The activity coefficient of NiO decreased with increase of basicity of melts and NaF generally added to enamel increases the activity coefficient of NiO. A relationship between the acitivity coefficient of NiO and optical basicity of melts was found and it is expected that optical basicity would be able to use to find an glass composition for enamel.
