A method for deoxidizing low-silicon steel using silicon alloys

Abstract

The invention relates to the technical field of steelmaking, in particular to a method for deoxidizing low-silicon steel using silicon alloys. In the production process route of converter-RH vacuum refining-slab continuous casting, add Silicon alloy is used as a deoxidizer to remove the excess oxygen in the ultra-low carbon steel in the converter area and the excess oxygen after RH decarburization. The specific implementation steps are as follows: 1) The converter process requires boiling tapping, and ferrosilicon is added during the tapping process for deoxidation; 2) During RH treatment, ferrosilicon is used for pre-deoxidation; 3) After RH decarburization, aluminum is added for final deoxidation. The critical oxygen content can be calculated as 0.045%, and the composition is adjusted. Compared with the prior art, the beneficial effect of the present invention is that the silicon alloy (ferrosilicon) is used to remove excess oxygen, the silicon content of molten steel can be controlled below 0.030%, and the Al in the slab can be reduced while achieving the same deoxidation effect. 2 o 3 Increase the number of inclusions while reducing the cost of deoxidized alloys.

Description

technical field [0001] The invention relates to the technical field of steelmaking, in particular to a method for deoxidizing low-silicon steel by using a silicon alloy. Background technique [0002] In the production of ultra-low carbon steel such as cold-rolled IF steel and silicon steel in the converter, in order to ensure the oxygen content requirements and strict phosphorus content requirements for deep decarburization of RH, the carbon content at the end of smelting is controlled at a low level. The station adopts the method of feeding aluminum wire to control the oxygen content to between 450~650ppm. [0003] Oxygen in the steel at the end of converter smelting is the main source of oxide inclusions. Whether it is to produce ultra-low carbon steel or low-carbon steel, aluminum alloys are generally used to adjust the oxygen content, resulting in Al in slag 2 o 3 Higher, the cleanliness of the steel decreases, resulting in Al in the slab 2 o 3 The relative increase ...

AI Technical Summary

Problems solved by technology

Since ultra-low carbon steel requires less silicon (≤0.030%), the use of silicon alloys for deoxidation can easily lead to silicon increase in molten steel, so no one has tried to use silicon alloys as deoxidizers for converter steelmaking.

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