A large-capacity smelting and composition control method for ultra-high manganese twip steel

Abstract

The invention discloses a large-capacity smelting and composition control method for ultra-high manganese TWIP steel. The formula of the ultra-high manganese TWIP steel is: by mass percentage, C 0.6%-0.9%, Mn 20%-30%, Si 0.3%~1.0%, Al 0.3%~1.0%, P≤0.015%, S≤0.005%, V 0.3%~0.6%, Nb 0.2%~0.5%, impurity≤0.1%, the balance is Fe; according to the formula , the steel, metal vanadium and metal niobium are first smelted, and then the molten steel is refined and alloyed, then vacuum degassed, poured into steel ingots, and forged into forging billets. The invention realizes large-capacity, low-cost, and purified smelting of ultra-high manganese TWIP steel under general industrial production conditions, and the smelted ultra-high manganese TWIP steel has reached the level of vacuum furnace smelting in terms of metallurgical quality and mechanical properties. Level.

Description

technical field [0001] The invention relates to the technical field of ultra-high manganese alloy steel smelting, in particular to the large-capacity smelting and composition of an ultra-high manganese TWIP steel (the ultra-high manganese TWIP steel refers to twin-induced plasticity steel with a manganese content ≥ 20wt.%) control method. Background technique [0002] With the increasingly prominent energy and environmental issues, lightweight has become the development trend of modern automobiles and other vehicles, which has higher requirements for the strength and toughness of steel used in vehicles. In addition, in order to improve the passive safety performance of automobiles, the steel used in automobiles needs to have the highest possible energy absorption capacity, that is, have high strength and plasticity. In order to achieve these goals, in recent years, major automobile steel manufacturers and research departments in the world have been developing steels for aut...

AI Technical Summary

Problems solved by technology

[0004] Generally, ultra-high manganese TWIP steel contains high concentration of volatile element Mn and oxidizable element Al. During the high-temperature smelting process, Mn volatilization and Al oxidation are very serious, and the C content is very low, so it can only be used under the protection of an inert atmosphere in a vacuum furnace. Smelting is not only costly, but also difficult to achieve large-scale large-scale production

Secondly, due to the strong chemical activity of Mn and Al, it is very easy to have complex physical and chemical reactions with the melting atmosphere and lining materials during the melting process, resulting in a large number of non-metallic inclusions, which makes it very difficult to precisely control the purity of the melt and the composition of the alloy. difficulty

In addition, due to the large density difference between Al and Fe, macro-segregation is also very serious during solidification, resulting in poor uniformity of material structure and properties.

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