SU950509A1 - Electrode coating composition - Google Patents

Description

(54) COMPOSITION OF ELECTRODE PICTURE

one

The invention relates to welding, in particular to welding materials, namely to the composition of the electrode coating. The composition of the electrode coating ij, containing the following components, is known. %

Metal carbonates of them marble30 - 42

Dolomit5 - U

Fluorspar20-35

Manganese4-8

Chrome 4-8

Molybdenum 3-8

Mica1.5-3.5

Potash Oh 2-0.9

However, the known composition of the electrode coating does not provide sufficient heat resistance of the weld metal.

Closest to the proposed composition is an electrode coating of 2 J, containing the following components, by weight,%:

Fluorspar31.5 - 5O

Marble26-30

3.5-5.5

Manganese 0.4 - 1

Soda 17-24

Chrome 2-4

Mica 1-4

Aluminum

However, the known electrode coating does not provide sufficient heat resistance of the weld metal, and also has a tendency to embrittlement.

The aim of the invention is to increase the heat resistance and reduce the tendency of welds to embrittlement. The goal is achieved by the fact that the composition of the electrode coating, containing marble, fluorspar, chromium and a component containing aluminum, contains ferrochromborum, chromium in the form of nitrided ferrochrome, as a component containing aluminum, aluminum oxide, in the following ratio of the component, weight. %: Fluorspar17-19

Nitrided ferrochrome 8-11 Ferrochrombor23-27 395 Aluminum oki 17-23 MpaMo | jRemains When welding high-chromium steels of ferritic grade 15X25T, X2705T and others, as a result of the welding thermal cycle, the tendency to intensive grain growth and related embrittlement weld metal. To eliminate this negative effect, alloying elements are introduced into the weld seam, which contribute to the formation of a ferrite-austenitic structure. In the test electrodes, the chrome type wire Sv-06Kh25N12To was used as the electrode rod. Nickel, which passes from the wire to the weld metal, contributes to an increase in ductility and to the formation of an austenitic structural component. Chromium has the ability to form a dense gas-tight film at high temperatures. To increase the heat resistance of the weld, the content in the weld metal should be no less than in the base metal. This requirement is achieved by addition of nitrated (8–11%) and ferrochromboron (23–27%) ferrochrome (23–27%) into the electrode coating, which contributes to 27–29% chromium in the deposited metal. The introduction of ferrochromboron (23-27%) in the coating ensures the production of boron in the weld metal in the amount of 0.4-0.5%. Boron has a positive effect on the increase in heat resistance of welds when complexed with aluminum. In connection with this, the coating is elect. alumina (17–23%) was introduced in order to produce 3.5–4.0% aluminum in the weld metal. The use of nitrated ferrochrome contributes to an increase in the nitrogen content up to 0.01%, which increases the heat resistance of welds of welded joints of chromium steels. Thus, the additional introduction of ferrochrome (nitrided), ferrochromboron and alkali oxide into the electrode coating, as well as the use of a chromium-nickel rod, contribute to an increase in heat resistance, a decrease in embrittlement, and the production of high welding-technological properties of the welding electrode. Experienced electrodes, structural electrodes of which are presented in Table. 1 is made by the method of dipping, the weight ratio of the coating is 0.34 - 0.36. The welded joints are made of rods 0 12 mm of steel 127O5T under constant welding conditions: 1 85 - 90 A; Ug 28 - 32 V; direct current reverse-polarity, deposition rate of 10.9 11, 7 g / Ah. The chemical composition of the weld metal,%: $ 0.10 С; 0.6 - 0.7 Si; 0.8 1, 0Mv); 27.3 - 28.6 Cr; 6 - 7 N-i; 3.5 - 4.0 AC; B 0.5; 5 and P, O3; : L 5 0.01. Electrode rod Sv-06Kh25N12TO Note. Liquid glass 2OZ% of the dry weight of the mixture. Welded joints made by electrodes are tested under production conditions. The samples will be placed in the zone of the shaft furnace with a temperature of 12OO C. Testing of welded joints made of steel X27105T in a reducing environment shows good quality of the weld metal and high heat resistance. The weld metal of the seams, made by electrodes K. - K ,, has the best indicators of S resistance against a known electrode. Formula Composition of the electrode coating, mainly for welding high-chromium steels, containing marble, fluorspar, chromium and a component containing aluminum, differing in m, which, in order to increase heat resistance and reduce the tendency of welds to embrittlement, also contains ferrochromor , chromium in the bidet of ferrochrome is nitrated 59505 ngo, and as a component containing aluminum, aluminum oxide, with the “following ratio of components, weight,%: Fluorspar 17–19 Ferrochrome nitrogen-5 Aluminum oxide 17-23 MramyrOstalnoe 96 Sources of informassh taken into account during examination 1- USSR Author's Certificate No. 271687, cl. At 23 K 35/365, 1969. 2. USSR Copyright Certificate No. 414070, cl. At 23 K 35/365. 1972 HP

Claims (1)

Claim The composition of the electrode coating, mainly for welding high-chromium steels, containing marble, fluorspar, chrome and a component containing aluminum, characterized in that, in order to increase heat resistance and reduce the tendency of welds to embrittlement, it additionally contains ferrochromium, chrome in yide ferrochrome nitrated 5, and as a component containing aluminum, aluminum oxide, with (the following ratio of components, wt.%: Fluorspar 17 - 19 Ferrochrome nitrated Ferrochrombor Alumina • MramRr 8-11 23-27 17 - 23 Rest