SU1502626A1 - Charge for melting synthetic slag - Google Patents

Abstract

The invention relates to metallurgy, namely, to compositions of the charge used for smelting synthetic slag, and can be used in the foundry industry for smelting high-quality alloys. The aim of the invention is to increase the refining properties of slag and impart modifying properties to slag. The mixture for smelting synthetic slag contains, wt%: silicon carbide 6–12, fluoride schlat 3–7, complex alloy AMC 30–40, and limestone - the rest. The use of the charge makes it possible to reduce the content of sulfur and phosphorus in the metal by 50 and 20-30%, respectively, and also to improve the mechanical properties of the metal. 1 hp f-ly, 2 tab.

Description

The invention relates to metallurgy, in particular to the composition of the charge used for the smelting of synthetic slag, and can be used in the foundry industry for smelting high-quality alloys.

The purpose of the invention is to increase the refining properties of slag and impart modifying properties to slag.

The proposed mixture for smelting synthetic slag contains silicon carbide, fluorspar, limestone and complex alloy AMC in the following ratio of components, wt.%:

Silicon carbide 6-12 Fluorspar 3-7 Complex alloy AMS 30-40 Known to the rest

At the same time, the AMC complex alloy contains, wt%: aluminum 5-10, manganese 25-35, silicon 25-35, and iron else.

The positive effect of introducing silicon carbide into the mixture is that it provides an active process for reducing the metal from oxides in the first place, since the thermodynamic activity of carbon and silicon that make up the ingredient is high with respect to the metal oxides.

The presence in the proposed mixture of fluorspar in combination with limestone provides sufficient liquid mobility of the slag and its desulfurizing ability, and also helps to clean the alloy from non-metallic

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inclusions, gases and other harmful impurities.

The introduction of a composite AMC alloy containing 5–10% with A1, 25–35% Si, 25–35% Mn, and iron to the composition gives the synthetic fy slag modifying properties with

The proposed mixture was prepared by conventional technology, i.e. Large pieces of silicon carbide, fluorspar, complex AMC alloy and lime are crushed to a size of no more than I cm and thoroughly mixed.

From the prepared slag-forming 15 charge, the slag bath is led in an electroslag furnace, and then in a continuous process, the calculated charge for melting iron is introduced into the furnace (the ratio of slag-forming mixture / alloy to 20 for melting iron, 0.9-1.1: 10)

Meltings were carried out in a semi-single-phase electroslag furnace with non-consumable graphite electroacid as seen from the table. 2, the proposed charge allows a high degree of refining of the pig iron produced.

The use of the proposed mixture leads to an increase in carbon equivalent, however, the increase in the carbon content in the structure is accompanied by its grinding and it becomes more compact, the graphite score changes from GF2 to GF5, and the dispersion of filament increases from P 1,4 1.4 to P 1, 0 In general, the effects of desulphurization processes, removal of nonmetallic inclusions and structural changes increase the combination of the physicomechanical properties (G. G ,. a, E) and age

structural stability of cast iron in a wide range of temperatures under the conditions of repeated thermo changes. The reduction of iron oxides in synthetic slag (Table 1) suggests a high deoxidizing effect.

a house and a crucible made of graphite and iron reduction in

As can be seen from the table. 2, the proposed mixture allows for a high degree of refining of pig iron produced.

The use of the proposed mixture leads to an increase in carbon equivalent, however, the increase in the carbon content in the structure is accompanied by its grinding and it becomes more compact, the graphite score varies from GF2 to GF5, and the dispersion of perlite increases from P § 1.4 to P 1.0. In general, the effect of desulphurization, removal of nonmetallic inclusions and structural changes increases the combination of physicomechanical properties (G .G ,. a, E) and increases

structural stability of cast iron in a wide range of temperatures under the conditions of repeated thermo changes. A reduction in the content of iron oxides in synthetic slag (Table 1) indicates its high deoxidizing capacity and the reduction of iron in

tizirovannogo electrode. The furnace was connected to a TPO furnace transformer, 250/40 µm, having four voltage levels of 24.4; 28; 33 and 40 V and rated current 6200 A.

The compositions of the tested blends for the production of synthetic slag are given in Table. one.,

The amount of complex alloy AMC in the mixture and the content of components in it is due to the fact that the modifying effect and assimilation of the components of the proposed mixture were maximum, and the number of elements such as C and Mn in the iron would correspond to the specified chemical composition of the pig iron produced. In addition, an increase in the content in the mixture of AMC alloy, and in the alloy of AMC, such elements as A1 and Mn significantly increases the cost of the charge, deteriorating the mechanical properties of the pig iron produced.

The chemical composition, structure and properties of the pig iron smelted using the known flux and the proposed charge for smelting synthetic slag and the treatment of pig iron by it are given in Table. 2

cast iron

Claims (1)

1. A mixture for melting synthetic slag, containing limestone, fluorspar and carbon-containing material, characterized in that, in order to increase the refining properties of the slag and impart modifying properties to the slag, it additionally contains the AMC complex alloy - silicon carbide in the following ratio of components, us,%: Silicon Carbide 6-12 Fluorspar3-7 Complex Alloy AMS30-40 Known for the rest 2, The mixture according to p, I, characterized by the fact that neigh, wt.%: Aluminum Manganese Silicon Iron what alloy AMC co5-10 25-35 25-35 Else