Stainless steel refining method

Abstract

The invention relates to a stainless steel refining method sequentially comprising the steps that: 1, molten steel satisfying requirements of argon oxygen furnace smelting is added into an argon oxygen furnace; 2, decarburization is carried out, wherein in a blowing decarburization process in which oxygen and nitrogen are both blown by using a top gun and a bottom gun, lime and light-calcined magnesium balls are added, wherein an MgO content in slag is 6-8%; sintered nickel, high-carbon ferromanganese, and chromium-and-nickel-containing stainless steel are added in batches according to the component of the type of steel; and carbon content in steel is removed to a value no higher than 0.05%; 3, a reductive bottom gun only blows argon, and stirring is carried out; ferrosilicon is added for reduction; fluorite and lime are added, wherein CaO / SiO2 is 1.7-2.2, and a MgO content is 6-8%; and molten steel components are analyzed; 4, molten steel components are adjusted according to analysis result and the components of the steel type; and 5, tapping molten steel analysis is carried out; when molten steel component mass percentages reach the requirements of the steel type, tapping is carried out. With the stainless steel refining method provided by the invention, corrosion of furnace slag to furnace lining is reduced.

Description

technical field [0001] The invention relates to a method for refining stainless steel. Background technique [0002] In the existing stainless steel refining method, the lining of the argon-oxygen furnace is made of magnesia-calcium. In order to avoid the corrosion of the lining by the slag in the steelmaking process, a certain amount of slagging material containing MgO is usually added to the furnace to ensure that the MgO in the slag content, reduce the erosion of slag on the furnace lining, and increase the life of the furnace lining refractory material. At present, light-burned dolomite and lime are mostly used for slagging in the stainless steel refining process. The MgO content in light-burned dolomite is about 30%. A lot of slag is added, which is put into the furnace many times during the stainless steel refining process. The slag layer has poor air permeability and fluidity, which is not conducive to decarburization and the alkalinity of the slag is difficult to gu...

AI Technical Summary

Problems solved by technology

At present, light-burned dolomite and lime are mostly used for slagging in the stainless steel refining process. The MgO content in light-burned dolomite is about 30%. A lot of slag is added, which is put into the furnace many times during the stainless steel refining process. The slag layer has poor air permeability and fluidity, which is not conducive to decarburization and the alkalinity of the slag is difficult to guarantee, which accelerates the erosion of the furnace lining by the slag during the reduction period.