METHOD OF PRODUCING FREE-CUTTING STEEL AM-14 Russian patent published in 2011 - IPC B22D11/00 C21C5/52 

FIELD: process engineering.

SUBSTANCE: invention relates to metallurgy, particularly, to continuous casting from free-cutting steel. Proposed methods comprises smelting semi-finished product in steel-smelting unit, deoxidising steel by aluminium at outlet of steel-smelting unit, adding deoxidising components into ladle bottom zone for oxidising at optimum [Mn]/[Si]≤3 ratio, out-of-furnace treatment in blowing by argon and induction of calcareous-aluminous slag, adding powder wire with filler free sulphur after slag thickening by magnesite powder, subsequent addition of powder wire with filler MnBi, casting at continuous casting machine "to the level" to produce continuously-cast billet from free-cutting steel of the following composition, in wt %: carbon - not over 0.16; silicon - not over 0.35; manganese - 1.0-1.5; sulphur - 0.08-0.35; phosphorus - 0.06-0.15; aluminium - not over 0.03; bismuth - 0.06-0.12; iron and admixtures making the rest.

EFFECT: improved mechanical properties over entire cross section and volume of billet.

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