SU1219652A1 - Charges for alloying steel - Google Patents

Description

This invention relates to ferrous metallurgy, in particular, to the production of vanadium-containing steels in electric arc furnaces.

The purpose of the invention is to improve the galaxies of the smelting mode, expand the raw material base and reduce the cost of steel.

The amount of reducing agent (aluminum) present in slags of aluminum alloy production is determined from the conditions of complete reduction of vanadium, iron, manganese from vertical vanadium slag, steel deoxidation and heat generation due to the heat of exothermic reactions that is necessary for the rapid formation of liquid active slag and compensate for heat loss. The aluminum content below the lower limit does not provide the specified conditions, and the upper limit does not contribute to the improvement of process performance. The spack-forming components of slags from the production of aluminum alloys with this ratio contribute to the production of furnace slag with a low liquidus temperature and viscosity, which makes it possible to completely use fluorspar and intensify the interaction processes between the slag and metal.

So, when using the known charge, the viscosity of the slag formed (fluorspar consumption 3 kg / t) is 0.25 E-s / m, and when using the fluorspar offered without additives, 0.23 N-s / m.

Alumina, fluorides, potassium, sodium and magnesium chlorides are thinning agents; the content of the components of pshakov aluminum alloy production below the lower limit does not contribute to a visually decreasing viscosity and liquidus temperature of the slag mixture formed after the additive, their viscosity is 0.38-0.45 N. s / m, and the upper limit does not further reduce (viscosity of slags 0.18-0.21 N / s). Magnesium oxide in such limits reduces erosion of the lining and increases the basicity of the slag. With a content of 5% by 5%, the heat costs for melting the charge increase.

19652

The presence of silicon dioxide slags within the specified limits does not complicate the process of reducing vanadium, manganese, and iron, and the slag melting mode 5, and also does not affect the quality of the metal. Consequently, these properties, imparted to the furnace slag by the components of the charge, contribute to the improvement of the smelting mode and, due to the elimination of the consumption of fluorspar, with the cost of steel. In addition, in the composition of the charge can be used pshaki smelting of aluminum alloys, 15 which expands the raw material base of metallurgical production charge materials and allows the use of waste containing valuable elements.

20 determining the feasibility and manufacturability of the proposed mixture for steel alloying were carried out by its industrial tests using the compositions specified in Table 25. one.

PRI im p Grade 20GFL steel is smelted in a 5t electric arc furnace.

The alloyed alloying of steel by van-3Q diem is introduced during the recovery period of smelting in the form of a mechanical mixture of vanadium slag of a converter redistribution of the composition, wt%:

Vanadium thioxide 13.0-26.0 Silicon dioxide 12.0-26.0 Total iron 28.0-42.0 Calcium oxide Up to 4.5, Magnesium oxide 1.0-6.0

Manganese Oxide 5.0-13.0 Chromium Oxide1.0-5.0

Aluminum oxide 0.6-1.8 Metall inclusion 4.0-25.0

35

40

and slags of production of aluminum

Alloys composition, wt.%:

Aluminum 15-40

Aluminum oxide 20-45

Silicon dioxide 0.2-5.0 Fluorine-containing

connections 0.2-2.2

-

Sodium chloride, potassium, magnesium

(total) 8-28

Magnesium oxide 0.5-7.0

Oxides and chlorides of other elements Else

The consumption of vanadium slag is determined by the content of vanadium penadium in it and is 7-1 5 kg / ton.

When using for the alloying of steel three compositions of the proposed mixture (Table 1), the optimum content of vanadium (0.09-0.11%) is obtained with a high degree of its assimilation from converter slag. The mechanical properties and chemical composition of the smelted steel corresponded to the existing requirements, which is confirmed by the data in Table. 2

When using blend compositions with a component content different from the boundary values, a decrease in the degree of absorption of the wahiad is observed.

0.25 1.4 0.5 more than 0.13 0.04 0.04

219652

ICT is not observed to increase. In this case, the vanadium content may deviate from the optimum values, which, according to statistical analysis, leads to an unstable level of the mechanical properties of the metal.

The use of the proposed for alloying makes it possible to completely eliminate the additives of the deficient heat of the spar, thereby reducing the cost of steel and utilizing the waste accompanying deoxidizing agents and slag materials.

Table 1

table 2

Continued table. 2

410 610 19.5 38.5

430 630. 20.5 39.0 435 640 17.5 -25.0

Editor V. Petrash

Compiled by A. Pruss

Tehred L.Oleynik Proofreader A. Ferenc

Order 1235/36

Circulation 552

VNIIPI USSR State Committee

on affairs of invention. 1st and discoveries 113035, Moscow, Zh-35, Raushsk nab, d. 4/5

Branch PPP Patent, Uzhgorod, st. Project, 4

Continued table. 2

0.29

0.30 0.20

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Claims (1)

1. CHARGE FOR STEEL ALLOYING, by ed. No. 994567, characterized in that, in order to improve the slag mode of smelting, expand the raw material base and reduce the cost of steel, it additionally contains slags for the production of aluminum alloys, while vanadium slag and aluminum slag. alloys taken in the ratio, wt.%: Vanadium slag 38.4-55.0 Slag for the production of aluminum alloys Else 2. The mixture according to claim 1, characterized in that the slag for the production of aluminum alloys has the following chemical Aluminum Aluminum oxide Silicon dioxide Fluorine compounds Potassium, sodium, magnesium chlorides (total) Magnesium oxide Oxides and chlorides of other elements composition, May.%: 15-40 20-45 0.2-5.0 0.2-2.2 © 8-28 0.5-7.0 Rest