Preparation and properties of SnO-SnCl2-P2O5 glass

The glass forming region in the ternary system SnO-SnCl2-P2O5 has been determined. Glass transition temperature (T-g), dilatomeric softening temperature (T-s) of the glass, and the viscosity of the liquids in the binary SnO-P2O5 and SnCl2-P2O5 systems were measured. Compositional dependencies of these properties have been investigated. The T-g and T-s of the glasses and the viscosity of liquids for the SnO-P2O5 glasses increase linearly with increasing SnO content in a range of 40-60 mol% SnO. The substitution of chlorine for oxygen by increasing the SnCl2/SnO ratio results in a decrease of T-g and T-s of the glasses and the viscosity of the liquids. The T-g and T-s of the glasses and the viscosity of the liquids of the SnCl2-P2O5 system increase between 40 and 60 mol% SnCl2, are a maximum at about 60 mol% SnCl2, and then decrease with further addition. The SnCl2-P2O5 systems had a decreasing viscosity, which is not observed in the SnO-P2O5 and SnF2-P2O5 systems. The 70SnCl(2)-30P(2)O(5) glass, having a viscosity between 0.9 and 10 Pa a in a temperature rang of 500-600 K, would be useful in a practical application for sealing glasses. (C) 2001 Elsevier Science B.V. All rights reserved.