Smelting method of low-carbon aluminium killed steel with low silicon content

Abstract

The invention relates to a smelting method of the low-carbon aluminium killed steel with a low silicon content, belonging to the steelmaking technical field of the metallurgy industry. The technical scheme in the invention is as follows: before blast furnace vanadium-containing molten iron enters the steelmaking process, the processes of vanadium extraction and silicon removal are performed, the steelmaking process adopts the semi-steel smelting process, low-silicon pre-melted composite refining slag is added in molten iron during the slag-stopping tapping process, the deoxidizing process andthe alloying process for pre-deoxidation; after molten iron enters the ladle furnace (LF) refining process, the conventional mode for preparing white slag through electrode heating is not adopted, white slag is rapidly prepared by covering a cover for heat preservation and using aluminum powder as a deoxidizer in the reducing atmosphere of argon stirring; then calcium treatment and argon soft blowing are performed, the thermodynamic and dynamical conditions of the silicon kickback of molten steel are inhibited under the premise of ensuring the refining quality; and after the argon soft blowing of molten steel is completed, molten steel enters the continuous casting process. By adopting the method, the Si element qualification rate of the low-silicon and low-carbon aluminium killed steel is up to more than 98%; and as the refining electrode heating process is not adopted, the method is characterized by low energy consumption, environmental protection and low production cost.

Description

technical field [0001] The invention relates to a low-silicon-content low-carbon aluminum-killed steel smelting method, which belongs to the technical field of steelmaking in the metallurgical industry. Background technique [0002] At present, when iron and steel enterprises produce low-carbon and aluminum-killed steels with silicon content less than or equal to 0.03%, such as SPHC, 08Al and other steel types, they usually adopt the production process of desulfurization outside the molten iron furnace + converter smelting + LF refining + continuous casting. The biggest problem in the production process is that the Si content in the steel is difficult to control. Since the steel contains a certain amount of Al, the phenomenon of Si reversion is very easy to occur during the refining and reduction process of the LF furnace, causing the Si content of the finished product to exceed the standard. It can only reach about 83%-90%. Chinese patent application 200610166553.X, titled...

AI Technical Summary

Problems solved by technology

However, the above-mentioned process method is not suitable for blast furnace vanadium-containing molten iron to produce low-carbon, aluminum-killed steel with silicon content less than or equal to 0.03%.