METHOD AND CHARGE FOR MANUFACTURE OF STRUCTURAL CARBON STEEL WITH REDUCED HARDENING CAPACITY IN STEEL-MAKING ARC-TYPE FURNACE Russian patent published in 2014 - IPC C21C5/00 

FIELD: metallurgy.

SUBSTANCE: method and charge for manufacture of structural carbon steel with reduced hardening capacity involves loading to a steel-making unit of charge consisting of metal scrap and slag-forming substances, its melting, repeated slag removal and correction of its composition during a melting process to provide the melt with content of manganese, chrome, nickel and copper of not more than 0.1 wt % each, phosphorus - not more than 0.01 wt %, pouring of a semi-finished carbon product or blast-furnace steel-making iron in the quantity of 1.0-35.0 wt %, heating of the melt to the finishing beginning temperature, finishing of the melt as to composition and temperature by means of oxidising reactions using gaseous oxygen and energy of an electric arc, preliminary metal deoxidation with low-silicone ferrosilicium or ferroaluminium; with that, the melting process of metal is performed in the steel-making arc-type furnace (SAF), and its final finishing as to temperature and content of carbon, deoxidation and alloying is performed on a ladle-furnace unit (LFU) with further treatment in a vacuum vessel. Charge consists of metal scrap and a semi-finished carbon product or blast-furnace steel-making iron at further component ratio, wt %: metal scrap 65.0-99.0 and semi-finished carbon product or blast-furnace steel-making iron 1.0-35.0.

EFFECT: simpler manufacturing process, lower prime cost of steel and a possibility of its making using a semi-finished carbon product or blast-furnace steel-making iron.

3 cl, 1 dwg