SU620439A1 - Glass - Google Patents

Description

The invention relates to the composition of glass to be used for soldering with metals and alloys, in particular ala, from the preparation of various types of pressure seals with fittings from the 29K alloy. Known glass of the following composition weight. %: 60-70 20-25 2.0-5.0 O, 0-5.0 The closest in technical detail and comprehensible result to the invention is glass for soldering or covar alloy, including, by weight,%: 64 -68 ZitO2-4 LijO0,5-1,5 2. These glasses have a rather high coefficient of thermal expansion. The aim of the invention is to provide a coefficient of thermal expansion of glass in the range of (43-47/.10 .1 / deg. C). This is achieved by the fact that the known glass additionally contains ALPO with a blinding ratio of components weight. %: Sic, 65-69. 16-19.5 2.7-3.3 4.5-5.5 3.0-5.0 1.5-2.5 0.2-0.8 LNO0.8-2.2 The proposed glass is not crystallizes in the temperature range 4500 ° C; well wets grains of Ct-APjO at 7RO-.73O ° C. Due to this, a vacuum-tight homogeneous material is obtained, in which glass is dispersed strengthened by OC-AKjOs particles. Glass also has good adhesion to the Kovar alloy and good chemical resistance to water and acids, which makes it possible to obtain vacuum-tight heat-resistant junctions that are resistant in a humid atmosphere. Specific compositions of the glasses are given in b table. 1. Physical and chemical properties of the compositions of glasses are presented in Table. 2. The glasses were brewed in a gas oven of periodic operation in a ceramic vessel with a capacity of 36 O kg at a maximum temperature of 148 O ° C for 36 hours. Glass production was carried out in the form of a granulate during direct casting of glass into Water. A dried granule lt of glass was ground in a ball of chalk to produce a powder that was used in a mixture with alumina;; To obtain glass tablets by conventional powder technology. Glass-tablets of various sizes were directly sealed with alloy fittings, 29 NK to obtain multi-contact pressure seals of the type ТКЕ26П1Г and insulators of an electron beam gun. The obtained pressure seals passed with positive results of testing at a ten-fold temperature change of 300 minus 60 ° C, had an electrical resistance more rapidly after 10 days of moisture in the chamber and retained vacuum tightness after all thermal and mechanical tests. Offered glasses have a number of advantages over the known ones. Due to the low coefficient of thermal expansion and the presence of cotTflseMttO, they perfectly wet the L-AE O grains and allow to obtain Dispersed glass hardening with particles, besides, good adhesion to metal and high chemical resistance of the glass to water and acids allows to obtain vacuum tight heat resistant SpI, reliably I work in conditions of higher temperatures, low humidity and high mechanical load. Table 1

18.87 3.25.054.04

65.15

19.39 3, L4,53,20

66.96

16, O2,74,53,0

69, O

589

45 590 44 595 43

1.78 0.551.36

1.90 O, 2O, 85

2.0O, 82.0

Table 2

320

0.10.31 4.96 322

Claims (2)

O, 15 0.26 5.5 325 0.10.35 Claim of the invention Glass, including 5 Ol ZnO, K2O, UJijO, characterized in that, in order to provide a coefficient of thermal expansion 5 within / 43-47 /. 1O / 1grad.S, it additionally contains MmO in the following ratio of components, wt.%: SiOj65-69 b1616.5.5 cf, cl. 2.7-3.3 4.5-5.5 3, O-5.0 1.5-2, S 0.2-0.8 0.8-2.2 Sources of information taken into account expertise:. 1 .. Patent of England 11365О2, С -1 М, 1968. 2. US patent. 3420685, 106-54, 1969.