SU973630A1 - Slag forming mix - Google Patents

Description

The invention relates to metallurgy, in particular to the compositions of slag-forming mixtures used for treating metals. Slag-forming mixture known. containing the following components, wt%: Blast furnace slag 2.0-70 Sawdust 30-70 The disadvantages of this slag-forming mixture are the low basicity of the blast-furnace slag (0.74-1.26%), which causes its low reactivity; high content of c: ery in the domain of the donkey (0.51–2.91%), sharply limited; use of this mixture for metal processing due to the development of the resulfurization reaction. Slag-forming mixture 2, containing converter slag, 65% ferrosilicon and fluorspar at the following ratio of components, wt.%: Converted slag 65% ferrosilicon 8-15 Fluorspar. The rest, however, the slag-forming mixture has a high content of iron oxides, in the converter slag (12.80 - .25.14%), which leads to the secondary oxidation of the metal during the casting process, therefore, to deoxidize the converter slag, an increased consumption of ferrosilicon / deoxidation of the sinter is required. slag by ferrosilicium leads to an increase in the silica content in the donkey melt and a decrease in its basicity and, consequently, its reactivity. In addition, the cost of this mixture is very high and amounts to 24.6-48.3 rubles / ton, depending on the content of ferrosilicon and fluorspar in the mixture. The aim of the invention is to improve the reactivity of the slag melt and reduce the cost of the slag-forming mixture . This goal is achieved by the fact that the slag-forming mixture containing converter slag and fluorspar, additionally contains aluminum and white electric furnace slag in the following ratio of components, wt.%: White electric furnace slag 72.2-89.5 Converter slag 0.5-22, eight. Aluminum 0.5-1.0 Fluorspar, 5 The indicated amount of alumini ensures the recovery of the total content of iron oxides, which in the proposed mixture of steelmaking shpak is 2-4%, as well as the thermal effect of the reaction, necessary for the formation of liquid slag from high basicity The resulting reaction products of the oxidation of iron oxides by aluminum do not reduce the basicity of the resulting slag melt, which is favorably reflected in its reactivity. Taking into account that aluminum is more powerful and low-melting deoxidation than ferrosilicon and that the thermal effect of aluminum lacquer is higher than that of ferro-silicon, the amount of the mixture of steelmaking slags in the composition of the slag-forming mixture is reduced to 90-95%. The ratio of white furnace and converter slag was obtained, based on the following considerations. The total content of iron oxides in the slag should be 2-4%. The lower limit of SlFeO 2% provides the necessary thermal effect of the reaction, sufficient to produce a fluid molten slag. In addition, when the content of ElFeO is 2%, the slag-forming mixture slowly melts, as a result of which a significant amount of metal is not treated with slag. With a 4% PREOO content, the main liquid-fluid slag is quickly formed, however, a significant amount of aluminum is consumed for the reduction of iron oxides, which is economically unfeasible. Since the content of PREEO FeO + + is 1.35 FenOa in the white electric furnace putter is 0.51-1.88%, and the FeO content in the converter slag is 12.80-25.14%, to obtain IZFeO 2.0-4.0% the amount of white The electric furnace shpak in the mixture of steelmaking slags (90-95 wt.% of the total amount of the slag-forming mixture) should be 72.2-89.5%, and the amount of converter slag 0.5-22.8%. When casting metal on continuous casting machines, three mixtures were tested, as indicated in Table E.

80

Known

We propose the mixture to be deposited on the metal surface in an intermediate ladle of UNRS in the amount of 2% by weight of the metal. At the same time, the steel in the tundish was additionally purged with argon from the bottom in order to more fully utilize the reactivity of the slag melt. The data in the table show that the treatment of the metal with slag-forming mixtures is accompanied by a decrease in the content of sulfur and non-metallic inclusions. Metal processing of the proposed slag-forming mixture allows

0.067

24.0

10 to obtain a metal that is cleaner in non-metallic inclusions and with a higher degree of desulfurization than the known one. The cost reduction of the slag-forming mixture is achieved by reducing the consumption of deoxidizing agent AND fluorspar. The proposed slag-forming mixture provides a high degree of desulfurization of steel, a deeper degree of refining of metal from non-metallic inclusions, and ensures the integrated use of metallurgical slags.

Claims (2)

Invention Formula The spak-forming mixture containing converter slag and fluorine impregnation, so that, in order to improve the melting capacity and reduce the cost of the mixture, it additionally contains alcumin and white electric furnace slag at the following ratio of componenton, wt.%: 10 White elektropepP slag72,2-89,5 Converter ass 0.5-22.8. Aluminum 0.5-1.0 Fluorspar 4.0-9.5 Sources of information that are considered in the examination 1, USSR Author's Certificate 719791, cl. B 22 D 7/00, 1978. 2. Authors certificate of the USSR 558541, cl. C 21 C 5/54, 1975.