PROCEDURE FOR MELTING ALLOYED STEEL CONTAINING NITROGEN Russian patent published in 2011 - IPC C21C7/00 

FIELD: metallurgy.

SUBSTANCE: procedure consists in deoxidisation of liquid metal, in its alloying with elements increasing nitrogen solubility, in blasting melt with nitrogen containing gases at intensity l/t·min at rate of saturation v_N=8×(|Cr|+|Mn|), ppm/min. Also, time of saturation is τ=[ΔN]/8×(|Cr|+|Mn|), min, where: |Cr|, |Mn| are absolute values of chromium and manganese contents in melt, wt %, [ΔN] is amount of nitrogen introduced into melt, ppm. Gaseous nitrogen or nitrogen-oxygen mixture, or nitrogen-argon mixture are used as nitrogen containing gas.

EFFECT: reduced time for nitriding, wear of lining, and consumption of ferro-alloys due to reduced melting loss of alloying additions.

4 cl, 3 ex