Physical-Chemical Properties of Low-Melting Phosphate Glasses in Relation to Tin Oxide Content

Abstract

The influence of SnO on the physicochemical properties of low-melting glasses in the system Li₂O–SnO–P₂O₅(LSP), intended for use in compositions for vacuum-tight low-temperature bonding of different materials, was studied. The low values of T_g promoted high spreadability of LSP-glass powders at temperatures below 450°C (typical for gluing electronic articles). The mass losses upon boiling of LSP-glasses varied over a wide range (0.19 – 4.55%), and in terms of chemical resistance the glasses characterized by mass losses below about 3% surpass the lead-borate glasses widely used in solders. The values of ñ_v for LSP-glasses were raised to values characteristic for lead-borate glasses by optimizing the alkali-content ratio.