Deoxidation method of aluminum-killed silicon-containing steel

Abstract

The invention discloses a deoxidation method of aluminum-killed silicon-containing steel. The deoxidation method comprises a converter smelting process, an LF furnace refining process and a refining process, wherein the converter process specifically involves that a silicon-containing deoxidizer is adopted for deoxidation in a converter tapping process, after tapping is completed, a top slag modifier is added to the surface of molten steel, 400 + / -25 kg of the top slag modifier per converter is added, the top slag modifier comprises of, in percentage by mass, 9% + / -1% of Al2O3, 27.5% + / -1.5% of CaO, 3% + / -1% of SiO2, 50% + / -2% of Al, and 7% + / -1% of CaF2; and the refining process spedifically involves that deoxidizing and slagging are conducted by adopting an aluminum deoxidizer. According to the deoxidation method, through the two-step deoxidation process, the deoxidation cost is greatly reduced, meanwhile, the molten steel quality is improved, and as inclusions formed in the molten steel by silicon deoxidation are easier to float upwards compared with aluminum deoxidation, the purity of the molten steel is also improved, and the molten steel quality is improved.

Description

technical field [0001] The invention belongs to the technical field of steelmaking in the metallurgical industry, and in particular relates to a method for deoxidizing aluminum-killed silicon-containing steel. Background technique [0002] At the end of converter steelmaking, excess oxygen is dissolved into molten steel, and the excess oxygen precipitates out to form oxide inclusions and bubbles when the molten steel solidifies, and the resulting oxide inclusions remain in the steel, which will reduce the plasticity, impact toughness and other mechanical properties of the steel. High oxygen content will also produce defects such as subcutaneous bubbles and porosity, and aggravate the harmful effects of sulfur, directly affecting the quality of billets and steel products. At present, the deoxidation method of steel smelted in steel mills is generally based on aluminum-iron deoxidation. The advantage of aluminum deoxidation is that the aluminum grains are finer and the deoxida...

AI Technical Summary

Problems solved by technology

At present, the deoxidation method of steel smelted in steel mills is generally based on aluminum-iron deoxidation. The advantage of aluminum deoxidation is that the aluminum grains are finer and the deoxidation effect is very obvious, but the disadvantage is that the cost of aluminum-iron deoxidation is high, and aluminum deoxidizer is easy to form Al 2 o 3 The inclusions cause water blocking or no downflow, so a new deoxidation method is needed to reduce the cost of deoxidation

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