SU948918A1 - Low-melting glass - Google Patents

Description

one

FIELD OF THE INVENTION The invention relates to compositions of pegcoped glasses used as insulating coatings on the 4th frame, molybdenum electrodes in. sensors of the redox potential of liquid media, as well as in electronics, technology of vacuum materials, technology of ceramics and other areas of technology, where such glasses are used as solder materials, inorganic adhesives, glazes, and colored enamels for marking metal products, semiconductors, ceramics, proton-oxidative and zapstnya POSITIONS FOR metals and alloys, the linear linear thermal expansion (CTE) coefficients of which lie within (45-65) S K

one

Known low-melting glass trace of the composition, weight. %:

S-IO 15-55

,, 0.1-0.6

VaOg0,8-6

PbO30-65

Nai O2-6

404-9

ZnOO-6

The closest to the invention to the technical essence and the achieved result is a glass With the following composition, weight. %:

SiOQ 7-14

BG OZ18-32

to

ZnO34-46

Pt D11-29

Cu8-16 2

The CTE of this glass in the range from O 5 to 425 Рс lies within (45-65) l, and the temperature of the onset of softening is 550-600 C.

However, these glass tfigodnye in tehnopogtaz of vacuum materials can not be applied when kzgotovle cc medshshnskogo equipment where the glass pegkoplavkve can be iskhyupzova s as adhesives dd soedznvnv tungsten, molybdenum and other electrodes with a high-melting glass, and as germotikov and isopentane ruyupshh coatings on these and other metals and alloys used, for example, as comparative electrodes with a compensating correction for pH in the sensor of the redox potential of liquid media. OcHOBHbiM the disadvantage of these glasses is the relative high temperature of the onset of softening, which in the case of its use as adhesives leads to undesirable deformations at elevated temperatures of other glasses used in mechpodfp designs, to porosity and insufficient junction strength. Moreover, they have a fairly high crystallization capacity, which impairs glass adhesion to metal, coating uniformity and overall spa quality. The aim of the invention is to reduce the temperature of the onset of softening and the crystallization capacity. The goal is achieved by the fact that the glass, including 3i 0.2, BrOj, PCO, 2PO Cu O, additionally contains CoO in the following ratio of components, nantov, May. %: SiOtj15-20 64.02,30-5O P-LO30-42 ZnO2-3 CuO1. Ig NaqiO1 .. CoO1 s To obtain glass, a mixture of lead oxide (chemically pure) boric anhydride (x.4.) Is prepared, anhydrous kremnekis oty (h.ch soda {x.4.),. Copper oxides (h.ch.), lump oxide (x, h), cobalt oxide (h.ch.). The mixture is thoroughly mixed in a drum mixer for 30 minutes, then melted in a corundum crucible at 1250–1300 ° C in a sieve furnace for 1 h, after which the melt is cast on a metal stand, annealed from room temperature to 420–45 ° C to room temperature. . In tab. 1 shows the composition of gfedlagimyh stems. In tab. Figure 2 shows the physical and phytochemical properties of glasses. The application of an insulating coating of synthesized SUSH stack with tungsten jj and molybdenum1) 1e electrodes (in the form of wire) was carried out in two ways - powder and From a melt. In the first case, the annealed pieces of glass of these compositions were crushed first in an Abikh mortar, then in an agate mortar before passing the powder through a 0063 sieve (10,000 LTB / cm 2), after which the last fraction was further micronized in a UZDN-1 UCh2 ultrasonic disperser. From the dispersed product obtained, a fraction of about 1 micron in size was prepared using the method of sedimentation analysis. On the basis of this fraction, pastes were prepared, they were dipped into molybdenum or all-wire wires, which were then suspended in a muffle furnace, heated to a temperature of 720-840 ° C and kept at these temperatures for half an hour, after which another furnace was carried out annealing vitrified wires at temperatures of 450-48 ° C, followed by cooling to room temperature. The melting of glassy coatings was carried out as follows. A quartz glass was stuffed into a quartz tube, and then the tube was placed in a miniature electric furnace heated to temperatures of 10 ° -1O-50 ° C. At the same time, the glass turned into a relatively low-viscous melt, through which tungsten or molybdenum wires were drawn for 2–3 min. During this period, a uniform vitreous coating with a thickness of up to 0.1 mm was formed on the wire. Then annealing from a temperature of 45 ° -480 ° C to room temperature followed. The wires were then polished from the ends and used as a comparative electrode in the sensors of the redox potential of various microbiological systems. Testing of such sensors showed an increase in their sensitivity by 1.2-1.3 times as compared with previously similar sensors with epoxy coatings on electrodes, a sharp increase in the service life while maintaining calibration parameters, and also revealed the possibility of multiple and they are known to wear hot and cold ways.

Components, May. %

Table

The compositions

23

6

The temperature of the beginning of softening, ° С

460 475 483 485 490 495

Application temperature

porphyry coatings

by the method, ° С720 740 780 780 820 1О2О 1ОЗО 1О40 1О4О 1050. 1035 CTRD, d-lO to 65.1 62.6 54.4 59.5 Density, kg / m 3460 ЗЗОО 319О 3120 Crystallization capacity Lack of (no signs, Cree at 490-840 C for 1 h. Chemical resistance E to chromium mixtures kg / msec-10 4.7 4.2 4.1 4.0 Adhesion to metal, ceramics

.Table 2

55O-600

900-950

Claims (2)

840 High 45-65. 47.3 52.1 44OO-48OO 760 2790 l from the tent of the krasschelt-o 5.6-7.1 1.7 2.8 Good 794 Claims of the invention Lepty glass, vypochechayuschee 5iO. In the open, rino, soo 7 is different, tjro, with l 1 t tt t / "t ... A. In order to reduce the temperature of the wa of the softening and crystallisation ability, it is supplemented with the contents and CoO at the following ratio of components, May. %: I d 15-20 ° в9186 РЬО30-42 Сио C.UO NaqOlit CoO Sources of information: atsii, 1: worn into account during examination 1. Japanese patent M 49-36808, yu kp. 21 A 296, pubic. 1974. 2. US patent number ZO8883 3, - 106-49, published. 1960 (protohote).