Alkali-free phosphate glass and preparation method thereof

Abstract

The invention relates to alkali-free phosphate glass and a preparation method thereof. The glass comprises the following components in percentage by weight: 30-57% of P2O5, 8-30% of ZnO, 15-45% of SnO, 15-40% of B2O3, 1-4% of SiO2 and 1-8% of Al2O3. The preparation method comprises the following steps of: (1) uniformly mixing all components, and melting the mixture in a silicon carbide rod furnace to obtain a glass liquid; (2) forming the molten glass liquid in a preheated die, annealing and cooling the die, and finally machining and forming to obtain the alkali-free phosphate glass. The alkali-free phosphate glass does not contain alkali or lead, so that the electrical insulating property of electronic devices is ensured, and the glass is friendly to the environment. The hermetical sealing temperature and the thermal expansion coefficient of the glass meet the low-temperature sealing-in requirement on electronic parts and components, the chemical stability is good, and the glass can be applied to the sealing-in and sealing of electronic components such as diodes, silicon controlled components, and the like. The preparation method has the advantages of simple process, low cost andgood application prospect.

Description

technical field [0001] The invention belongs to the field of phosphate glass for electronic components, in particular to an alkali-free phosphate glass and a preparation method thereof. Background technique [0002] Because lead glass has properties that other glass components do not have, it can be made into crystal glass, optical glass, electrical glass, protective ray glass, and welding glass for electronics. Among electrical glasses, lead glass is suitable for mechanical molding of light bulbs, and Dumet wire with iron-nickel alloy as the core and copper sheath is used as the lead wire, which can be stably sealed with lead glass. At the same time, lead glass is also used in electric lamps, fluorescent lamps, cathode ray tubes (CRT) and various electronic tubes. In addition, it is also used to accommodate the neck of the electron gun of the cathode ray tube and the manufacture of the cone of the color picture tube. with PbO-B 2 o 3 -SiO 2 It is a solder glass made of...

AI Technical Summary

Problems solved by technology

[0006] Contains P 2 o 5 -B 2 o 3 -SiO 2 The glass system is prone to phase separation or crystallization during melting. Since they are all glass formers, they compete for oxygen ions at high temperature. In order to suppress this tendency, alkali metal oxides are often added to the glass, but adding On the one hand, the alkali metal oxide will greatly reduce the resistivity of the glass and deteriorate the insulating performance of the glass. On the other hand, it will also increase the thermal expansion coefficient of the glass, so that this alkali-containing material can only be used with some metals.