Description

The Borosilicate glass composition doped with sodium silico fluoride has been developed which was more refined, free from seeds, bubbles and cords. Addition of fluoride compound accelerated the glass melting but viscosity and surface tension was reduced. Many variations have been made in standard borosilicate (7740) glass composition to develop a new composition which was melted according to the conditions economically available. Electrical furnace with stirring system was highly expensive which was not feasible for the Pakistan to develop such a highly expensive glass. So a gas fired furnace without stirring system at comparatively lower temperature was used for the melting of theses glasses instead of electric furnace. This glass was developed first time in Pakistan at laboratory scale within our country resources and available facilities.