The wetting of three component silicate glasses on platinum

Measurements of the contact angles of sessile drops of alkali silicate glasses, containing other oxide additions, on platinum have been used to study the role of the glass composition in the wetting processes. A model has been proposed which relates the degree of wetting to the competition between the substrate metal and cationic and anionic groups in the molten glass for the valency electron of non-bridging oxygen ions. An empirical relationship between equilibrium contact angle and the affinity for oxygen ions of cations in the glass supports this model.