Multifunctional composite refining agent for steel-smelting

Abstract

The invention provides a multi-functional refining agent which can effectively control inclusion in steel. The refining agent consists of CaO, CaC2, SiC, Na2CO3, C, CaF2 and BaCaSi alloy, wherein the weight percentage of the refining agent is: 30-60 percent of the CaO: 5-15 percent of the CaC2: 5-15 percent of the SiC: 5-15 percent of the Na2CO3: 5-15 percent of the CaCO3: 5-15 percent of the CaF2: 2-10 percent of the BaCaSi: 2-10 percent of the C; the melting point is less than or equal to 1400 DEG C. The refining agent has the functions of wiping off the inclusion in the steel, expanding foam for submerged arc and removing sulfur. After being matched with the complex refining agent, the T(O) in finished steel is declined to the range of 5 multiplied by 10<-6> to 15 multiplied by 10<-6>, and the evaluation grade of the inclusion of B, C and D class is less than 1.0 grade with good sulfur removal effect as well.

Description

technical field [0001] The invention relates to a refining agent for steelmaking, which belongs to the field of refining molten steel outside a furnace, in particular to refining molten steel when high-quality molten steel is smelted by a converter process. Background technique [0002] Because the oxygen blowing operation in the furnace during converter steelmaking will cause a large amount of Fe in molten steel to be oxidized into FeO, which will lead to a substantial increase in FeO in converter slag, and a large amount of converter slag will inevitably be brought into the ladle during converter steelmaking , and finally make the FeO of ladle slag in a higher range. Ladle slag with high FeO content has the ability to transfer oxygen to molten steel again, increasing the total oxygen content of molten steel and deteriorating the quality of molten steel. At the same time, in the deoxidation alloying of medium and high carbon steel, a large amount of Si-containing alloys su...

AI Technical Summary

Problems solved by technology

Although this process reduces the FeO in the ladle slag, the S content in the finished steel reaches 0.005%-0.0012% (0.009% on average), and the T[O] content reaches 15×10 -6 ~34×10 -6 (average 24×10 -6 ) level, but submerged arc slag and refining agent are required to be used together during production, which is extremely inconvenient for production operation and management, and there is still a large gap between the T[O] content and the requirements of high-quality molten steel, and there is no report on inclusion control

[0006] In short, the current refining agent has a single function, and it is difficult to play a greater role in the production of high-quality steel

Images