SU948590A1 - Electrode coating composition - Google Patents

Description

(54) COMPOSITION OF ELECTRODE POINTING

one

The invention relates to the field of welding, in particular to welding materials, namely, to the composition of the electrode coating, which is used mainly for welding of multi-alloyed and low-alloyed steels.

Various electrode coatings are known, for example, composition f1, containing the following components, wt%:

MarbleSog-50

Fluorspar5-20

Quartz sand1 - 10

Ferromanganese2-10

Ferrosilicon2-15

Zirconia 3-20

Stavrolit1 -3

Mica1 -6

Cellulose4-5

The coating is applied to a low carbon rod.

The disadvantage of this electrode coating is a high content of hydrogen in the weld metal (5-7 cm per 100 g of weld metal), which leads to a decrease in the efficiency of the structure.

Closest to this composition is the electrode coating 2, containing the following components, wt.%:

Fluke pshat15-25

Rutile2-10

Ferromanganese2-8

Ferrosilshay3-10

Ferrotitanium1-3

Silicon dioxide 1-3

Soda Ash 1-4

ten

Lanthanum oxide2-5

Aluminum Powder1-3

Iron powder 20-40

MarbleEverything Else

Electrodes with this coating allow

ts to produce welding on alternating current, more technological in manufacturing.

However, these electrodes have the following disadvantages of the coarse-drop transfer of the electrode metal, the formation of undercuts during

20 welding, a sharp transition from the base metal to the weld metal, as well as attacks in the mechanical properties of the weld metal, especially when using rods made of steel Sv-08, which is characterized by a high content of sulfur and phosphorus (compared to the core of steel Sv-08A ). The coarse transfer of the electrode metal complicates its metallurgical processing (removal of sulfur to phosphorus) and worsens the formation of a weld. Sharp transitions from the base metal to the weld metal, attacks in the mechanical properties and undercuts significantly reduce the performance of the welded structure. The aim of the invention is to increase the strength of the metal lUBa (no undercuts) and improve the formation of the weld metal. To achieve this goal, the composition of the electrode coating, containing marble, fluorspar, a component containing titanium dioxide, ferromanganese, ferus aluminum, and iron powder, contains a component selected from rpynmiT silymanite, kaolin, potassium-sodium silicate lump potash, and an organic plasticizer , and as a component containing titanium dioxide - ilmenite, with the following ratio of components, wt.%: Marble15-30 Fluorspar15-25. Ilmenite5-15 Ferromanganese4-8) errosilicon3-10 Aluminum1-3 Iron powder20-35 Component selected from the group of silymanite, kaolin 1-9 Potassium-sodium silicate lump1-3 Potash1-4 Organic plasticizer To use the described composition of the electrode coating for welding structures, operating at low temperatures, it is necessary to add cerium fluoride in the amount of 0.5-5 wt.%. To obtain stable mechanical properties of the weld metal (when using steel Sv-8 stitches), it is necessary that the thermodynamic activity of the components that bind sulfur be minimal. To obtain atomized transfer of the electrode metal and a smooth transition from the base metal to the weld metal, it is necessary to reduce the surface tension of the slag and improve the wettability of the metal. As studies have shown, the introduction of compounds containing NajO, SiOj to the composition of the calcium fluoride coating most strongly reduces the surface tension of the slag and simultaneously stabilizes the burning of the arc and contributes to the small-drop transfer. Moreover, the introduction of sodium-potassium-silicate compounds such as silimanite, kaolin, and sodium-potassium lump is most appropriate, since they significantly improve the pressing properties of the coating. Replacement of rutile with ilmenite contributes to a better wettability of the metal with slag and, consequently, a smoother transition from the base metal to the welding seam. At the same time, SiOj and TiOj significantly reduce the thermodynamic activity of ferrous oxide, which contributes to an increase in the mechanical properties of the weld metal. Small-drop transfer of the electrode metal and reduction of the surface tension of the slag help to better purify the metal from impurities (sulfur, phosphorus). To improve the crimping ability of the electrodes, an organic plasticizer, such as cellulose, is introduced into the coating, and to reduce the hydrogen content introduced by plasticizers during welding of structures operated at low temperatures, cerium fluoride is added to the cdcTas coating. In the manufacture of electrodes, liquid potassium-sodium glass with a modulus of 2.7–3 was used as a binder. Pokrygty was applied on metal rods with a diameter of 4 mm from wire Sv-08 by means of crimping. To obtain the coating, 4 formulations are prepared and tested, given in Table. I. Table 1

When testing welding - technological dp chemical analysis (determination of sulfur

electrode properties and mechanical properties of phosphorus). As a source of pitash.

The weld metal was made by welding plates from a TSD-500 transformer. Strength

steel Art. 3 with a thickness of 14 mm. A plate of 35 welding currents was 160-200 A. Samples were made to test the mechanical properties of the metal of the isha and the chip was taken. The test results are given in Table. 2

The content of potassium-sodium lump in coco; 1-3% by weight is optimal. The increase in potassium-sodium lump more than 3% higher than hygroscopicity Continued table. one

Table 2

covered, and a decrease of less than 1% does not give a positive effect.

The content of lmanite or kaolin in the range of 1-9 wt.% Gives a large positive effect. Less than one percent of its effect on the physico-chemical properties of the slag is not significant, and more than 9 wt.% Increases the splashing of the metal. The content of cerium fluoride to 5 wt.% The most rational. An increase in its content of not more than 5 wt.% Increases the toxicity of the electrodes. The introduction of calcium fluoride into the composition of organic plasticizers (cellulose, etc.) is advisable up to 2 wt.%. A further increase reduces the impact viscosity of the metal at a negative temperature. Increasing the content of kaolin to more than 5 wt.% Impairs the manufacturability of the manufacture of electrodes (promotes cracking of the coating of the electrodes during calcination). The content of ilmenite, within 5-15 wt.%. Reduces the mechanical properties of the weld metal, less than 5 wt.% Does not give a significant positive effect. /. A wire 4 mm in diameter made of steel Sv-08 was used as the electrode rod. Electrode. The dashagm coating showed the following mechanical properties of the weld metal and the Weld joint in the state after welding at normal temperature: strength limit 520-540 MPa, relative elongation 23-29%, impact strength 150 180 J / cm. Electrodes ensured small-channel transfer of electrode metal, a smooth transition from the base metal to the weld metal, and the absence of undercuts when welding in forced modes. Electrodes with a coating - even for their composition are easy to manufacture and have improved fffi welding and engineering properties. They provide welding of Hbtx welds with a smooth transition to the base metal, not prone to the formation of undercuts. Production of electrodes does not require a change in the existing technology. The formula of the invention 1. The composition of the electrode coating, mainly for welding low-carbon and chiselled steels, containing marble, fluorspar, a component containing dioxide-titanium, ferromanganese, ferrosilicon, aluminum and iron powder, characterized in that, in order to increase the strength of the weld metal and improving the formation of the weld metal, the composition additionally contains a component selected from the group of silymanite, kaolin, potassium-sodium silicate lump, and organic plasticizer, and as a component with holding titanium dioxide, ilmenite, with the following component ratio, wt.% hydrofluoric Mramor15-30 shpat15-25 Ilmenit5-15. Ferromanganese4-8 Ferrosilicon3-10 Aluminum1-3 Iron powder20-35 Component selected from the group of silymanite, kaolin 1-9 Potassium-sodium silicate lump1-3 Potash 1-4 Organic plasticizer 0.5-2 2. The composition according to claim 1, characterized in that it additionally contains cerium fluoride in an amount of 0.5-5% by weight. Sources of information taken into account during the examination. I. USSR Author's Certificate No. 329988, cl. B 23 K 35/365, 1970. 2. USSR Copyright Certificate No. 651928, cl. 23 K 35/365, 1977 (prototype).

Claims (2)

Claim 1. The composition of the electrode coating, mainly for welding low-carbon and low alloy steels, containing marble, fluorspar, a component containing titanium dioxide. ferromanganese, ferrosilicon, aluminum and iron powder, characterized by heme, which, in order to increase the strength of the weld metal and improve the formation of weld metal, the composition additionally contains a component selected from the group of silymanite, kaolin, potassium-sodium silicate block, potash and organic plasticizer, and as a component comprising ilmanite-dioxide, in the following ratio of components, wt.% Marble15-30 Fluorspar15-25 Ilmenite 5-15. Ferromanganese 4-8 Ferrosilicon 3-10 Aluminum1-3 Iron powder 20–35 A component selected from the group of silymanite, kaolin 1-9 Potassium-sodium silicate block 1-3 Potash 1-4 Organic Plasticizer 0.5-2 2. The composition of the pop. 1, characterized in that it further comprises cerium fluoride in an amount of 0.5-5 wt.%. Sources of information taken into account during the examination. 1. USSR author's certificate No. 329988, cl. B 23K 35/365, 1970. 2. USSR Copyright Certificate No. 651928, cl. In 23 K 35/365, 1977 (prototype).