METHOD OF LADLE TREATMENT OF ALLOYED STEELS Russian patent published in 2017 - IPC C21C7/06 C21C7/76 

FIELD: metallurgy.

SUBSTANCE: invention can be used in production of grades of alloyed of steels with the content of carbon from 0.2 to 0.7 wt % including with increased sulfur concentration of 0.01-0.04 wt %. The method of ladle treatment of alloyed steels includes stepped introduction of deoxidizing agents and alloying components at outlet of semi-product into a steel-ladle with the subsequent supply of metal to continuous casting. The temperature and the active oxygen content of the semi-product at the outlet are 1600-1700°C and 0.030-0.075% respectively, primary deoxidation is performed with carbon-containing material preliminarily added to the bottom of steel-ladle, when the steel-ladle is filled with 1/6-1/5 of height, aluminium is added in amount of up to 3 kg/ton, when the steel-ladle is filled 1/2-2/3 of the height, the silicomanganese is added together with the second additive of the carbon-containing material, the alloying components are supplied in the form of master alloys and ferroalloys on the middle of the grade content of the components from the calculation of their total assimilation, and the calcium-containing materials are added to ladle prior to feeding metal for continuous casting.

EFFECT: invention makes it possible to obtain low contamination level of metal with non-metallic inclusions, including sulfide, silicate and spinel types due to optimisation of deoxidation processes, alloying of metal and modification with calcium-containing materials, and reduction of steel-melting defects due to increased stability of continuous casting.

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