SU1227316A1 - Slag-forming composition for casting steel - Google Patents

Description

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The invention relates to metallurgy, namely to the compositions of slag-forming mixtures used in casting steel into molds.

The purpose of the invention is to improve the quality of the ingot surface and reduce the content of non-metallic inclusions in steel.

The sponging mixture for casting steel is prepared as follows.

The use of the proposed blend of waste refining (linen) slag of the steelmaking industry has a high basis) in the slag contains, in%: CaO 35-46; Zgb 22-30, iron oxides 0.7-3.0, 5-10, CaPr. 7-17 ,, MgO 11-16) and has the property of self-scattering during the cooling process. Introducing it into the mixture provides easy peeling of the garnish from the walls of the mold formed in the process of combustion and melting of the mixture, and also helps to increase the refining capacity of the slag melt.

When the content in the mixture of spent (white) hat is less than 10%, self-dispersion and exfoliation worsens. garnish from the walls of the mold, the quality of the ingot surface deteriorates, and more than 40% deteriorate. Tesh7: About-o work profit.

The dump aluminum sack contains up to 35% free aluminum and 4.5% magnesium. In the mixture, he plays the role of the combustible component. The heat generated during the combustion of aluminum is spent on heating the components of the mixture, which speeds up the slagging process.

Manganese ore and sodium nitrate serve as oxidizing agents and provide components.

The content of components in the mixture,% 1 12 I 3 I 4 I 5

Fluorspar Manganese ore Natrium saltpeter

5 3

2

steady burning of the mixture during the casting process, When the manganese ore is not fully consumed, manganese oxides are dissolved in the slag, lower it

V513KOST.

Sawdust in the mixture reduces the consumption of slag-forming components; isolate the metal mirror from heat loss due to radiation. With the burning of HiiH sawdust, the porous texture of the combustion products is formed, which has a positive effect on the thermal insulation of the near part of the ingot.

The fluorspar in the mixture serves to liquefy the donkey, i.e. for the viscosity of the slag melt. The introduction of spent refining slag into the mixture, which contains a large amount of CaO in combination with smelter spar, increases the basicity of the slag formed during casting, thereby ensuring easy removal of the skull during the subsequent preparation of molds for casting. High slag basicity with low viscosity provides better assimilation of inclusions that pop up in the mold during the casting and solidification of the ingot.

In tab. 1 shows the compositions (1-4) of the proposed mixture, as well as lime: 1: oh composition (5), which were tested in the manufacture of ingots weighing 3.5 tons of steel grade 38XC.

The test results are given in table. 1 mixtures are presented in table 2

As follows from the table. data, the proposed mixture (compared with the known) provides a significant improvement in the surface quality of the ingots, as well as a decrease in the content of non-metallic inclusions in steel.

Table 1

15

3

ten

15 7 5 7 8 6

Dump slag aluminum production10

Wood sawdust datolit

40

Spent refining (white) slag steelmaking .34

Compiled by V.Malkov Editor A.Revin Tehred V.Kadar Proofreader I.Erdeyi

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VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, Projecto st., 4

Continuation of table 1

30 37

12 20

10 20

20 30 30

ten

40

42

Claims (1)

SLAG-FORMING MIXTURE FOR STEEL CASTING, including flux smelter, manganese ore, sodium nitrate, sawdust, aluminum slag dump, CaO-containing material, characterized in that, in order to improve the surface quality of the ingot and reduce the content of non-metallic inclusions in steel, it contains the quality of CaO-containing material contains spent refining slag of steelmaking in the following ratio of ingredients, wt.%: Fluorspar 5-15 Manganese ore 3-10 Sodium Nitrate 3-10 Sawdust 20-40 Aluminum dump slag production 10-30 Spent Refined roving slag steel- smelting production 10-40 SU ... 1227316 I 12273