Effect Of Certai Anions On Structural Transformations Of Silicate Glasses

The effect of anions (OH-, Cl-,F-,SO42-) on the ability of two silicate glasses to phase separate and crystallise has been studied. The compositions of the glasses were selected so that the initial specimens were homogeneous and contained 1 wt% of relevant anion. Electron microscopic and x-ray phase analysis revealed that phase separation accured between 450-600 C and was increased when anion impurity was added. however anion additives only influenced the crystallisation behaviour of one of the glasses.