Stanniferous ferrite stainless steel and smelting method therefor

Abstract

The invention relates to stanniferous ferrite stainless steel and a smelting method therefore. The stainless steel comprises, by weight, C 0.01 to 0.02%, Si 0.2 to 0.4%, Mn 0.3 to 0.7%, P 0.005 to 0.035%, S 0.001 to 0.005%, Cr 13 to 18%, Sn 0.1 to 0.5%, N 0.001 to 0.03%, Ti 0.15 to 0.3% and Nb 0.1 to 0.2%, with the balance being Fe and unavoidable impurities. The smelting method comprises the following steps in order: I, dephosphorizing desilicanized molten iron; II, carrying out smelting by the technology of K-OBM-S; III, carrying out refining by the method of VOD; IV, adding FeSn after refining in a furnace and regulation of slag are finished, wherein, the addition amount of FeSn is sufficient enough to enable the content of Sn in molten steel to reach 0.1 to 0.5%, and taking the molten steel out when the weight percentage of components in the molten steel meets requirements; V, carrying out continuous casting on the molten steel with components meeting requirements so as to obtain steel ingots. The stanniferous ferrite stainless steel smelted by the smelting method provided in the invention has good surface quality, deep drawing and formability.

Description

Technical field [0001] The invention relates to a tin-containing ferritic stainless steel and a smelting method thereof. Background technique [0002] In recent years, with the continuous growth of global stainless steel production, nickel resources have become less and less. The current global metal reserves are only about 60 million tons, and the average annual consumption is about 1.4-1.5 million tons. If used at this rate, the earth The nickel resources will be used up in 40 years. Even countries rich in nickel should study the rational use of nickel. Therefore, from the perspective of sustainable development, the development of alternative products for nickel-containing stainless steel has become the development trend of stainless steel. [0003] Ordinary ferritic steel has limited use due to poor workability. By reducing the carbon and nitrogen content in steel and adding stabilizing elements such as titanium to improve the workability of ferritic steel (ultra-pure ferriti...

AI Technical Summary

Problems solved by technology

However, the deterioration of surface properties caused by corrosion such as pitting corrosion and rust of ultra-pure ferritic stainless steel is often a problem.

In the reported Sn-containing steel patents, in order to ensure the processing performance and corrosion resistance of the product, the carbon content is required to be less than 0.01, which leads to serious oxidation of chromium in the molten steel during the refining process and increases the refining cost

Moreover, in order to ensure the corrosion resistance of the steel, the requirements for the titanium content in the steel are relatively high, the upper limit range reaches 0.5%, and the optimal range is also between 0.2-0.4%. Such a high titanium content in the steel can easily cause the continuous casting process. A series of problems, such as the blockage of the reclaimed water port and the fish formation in the crystallizer, have caused difficulties in the smooth flow of production