SU872010A1 - Exothermic slag forming mixture for casting steel - Google Patents

Description

one

The invention relates to ferrous metallurgy, in particular to mixtures for casting steel into ingots.

It is known to use as a slag-forming agent for dephosphorizing red sludge steel of aluminum production 1.

The disadvantages of red mud are that it has adverse physicochemical properties and melts relatively slowly in a mold.

Closest to the present invention is exothermic slag-forming mixture 2, containing, wt.%; Red mud production rjriHHO3eMa88

Exothermic reagent (aluminum powder) 2 Soda, potash, graphite 10 The disadvantages of this mixture are that potash and soda cause painful emission of gases during the use of the mixture during metal casting and worsen sanitary conditions at workplaces. The complexity of the mixture does not provide a stable composition during its production.

- The purpose of the invention is to reduce the melting temperature and viscosity of the slag.

and increasing the rate of slag formation.

The goal is achieved by the fact that iron oxide (RelO) is introduced into a mixture containing red mud from alumina production and an exothermic deoxidizing agent in the following ratio of components, wt.%:

Exothermic rac10

15-25 acidifier 1-4

Iron Oxide () Red Slime Production of Alumina

15

The presence of oxides of alkali metals, as well as oxides of aluminum and titanium in the composition of the slurry gives the mixture an increased refining capacity and rate of slag formation. The presence of an exothermic deoxidizing agent in the mixture, such as the self-dissolving alloy AMC, lowers the melting point and neutralizes the jelly in the red mud. The introduction of iron oxide () into the mixture sharply accelerates the combustion of the mixture and the rate of slag formation, reduces by 1-2 P the viscosity of the slag formed and its temperature

30 melting. An additive to a mixture containing red mud from alumina production and an exothermic deoxidizing agent, iron oxides allows an Exothermal reaction to take place at the initial contact between the mixture and the molten metal, thereby accelerating the melting of the mixture and the formation of living slag on the surface of the steel to be cast. The indicated contents of the components, together with the early formation of liquid slag, ensure the optimal level of its physicochemical properties. For use in the slag mixture, a red glass mill of the following composition is recommended, weight,%: CaO 30-39; Sio-z. 13-18; MgO 3-8; Ti Og. 2-6; Revision, 15-25; FeO 0.5-2.5; 4+ ..KjO 2.5-6.0. Powder shaped aluminum, silicocalcium, and manganese – silicon – aluminum alloys can be used as an exothermic molded body. Good results are obtained by using a self-spattering alloy A. Iron oxide is recommended to be used in powder form. The mixture may be used in the form of a powder of granules or briquettes. A suitable mixture is not only for steel casting, but also for insulating the profitable part of the ingots. Example. For the preparation of mixtures, red mud of the following composition is used, wt.%: CaO 38,32; SiO2.16,6; Al2.0-, 6.7; TiO 2. 2, 3; FeoFiu 19.04; 1.98; Redit 0,61; PaOp 0.202; S - 0.115; Na-jO +. 3.48; self-scattering alloy of AMC composition, wt.%: manganese 22.0; silicon 35.2; aluminum 8.9; iron else; iron oxide in the form of powder, formed during pickling of rolled metal. The table gives a comparative description of the mixtures: the proposed (1-3), known (4) and mixtures with a high content of iron oxide (5), as well as the physicochemical properties of the slags formed. As can be seen from the table, the proposed mixtures 1-3 ensure the formation of slags with the required level of physicochemical properties. The mixture 4, which does not contain iron oxides, is known, and the mixture 5, which contains an increased amount of them, does not meet the requirements for the basic physicochemical properties of slags.

Red mud production of alumina,%

Self-diffusing

Surface tension, mJ / m - 295

Interfacial tension, mJ / m 1070

Work adhesion, mJ / m -560

Liquid slag formation rate

c24

Claims (2)

The invention is an exothermic slag-forming mixture for steel casting, containing 80 76,5 74 390 327 980 1000 610 650 thirty red mud of alumina production and an exothermic deoxidizing agent, differing from the fact that, with the aim of reducing the melting temperature, the viscosity of the slag and increasing the slagging rate, 587, it additionally contains iron oxide in the following ratio, wt.%: Exothermic deoxidizer 15-25 Oxide of iron1-4 06 red mud of alumina production Else Sources of information taken into account during examination Japan Patent 51-40851, cl. 10 J 154, 1976. 2. The patent of Czechoslovakia No. 154441, cl. 31 at 7/10, 1971.