METHOD OF PRODUCTION OF LOW-CARBON SHEET STEEL Russian patent published in 2006 - IPC C21D9/48 C21C5/28 

FIELD: metallurgy; production of steel for enameled articles, automobile sheets of high degree of drawing and high-strength steel for automobile industry.

SUBSTANCE: proposed method includes regulation of nitrogen content and elimination of defects in micro-structure; proposed method consists in melting and teeming, hot and cold rolling and annealing. During teeming, required content of nitrogen is obtained by feeding it into jet of molten metal protected against air atmosphere at flow rate determined by the following dependence: Q_N=K₁(N₁-N₂)M_st, where Q_N is required flow rate of nitrogen, l/min; N₁ is required content of nitrogen in finished steel, %; N₂ is content of nitrogen in steel before delivery of metal into jet, t/min; K₁ is empirical coefficient taking into account hydrodynamics of interaction of nitrogen jet and jet of steel, as well as physico-chemical peculiarities of interaction of gaseous nitrogen and jet of molten steel within K₁=(0.13-50)X10³ l/%t.

EFFECT: enhanced efficiency.

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