INFLUENCE OF CARBON ACTIVITY ON A DEPHOSPHORIZATION DEGREE AT OUT-OF-FURNACE TREATMENT OF HIGH-ALLOY CHROMIUM MELTED STEELS

摘要

The extreme character of dependence of a dephosphorization degree from activity of carbon is experimentally determined for high-alloy of chromium steel melt The maximum of this dependence is necessary on values a (C) = 0,2/0.5 at the contents in a melt 5 percent Cr and a(C) = 0,2/0,3 at 25 percent Cr. The maximal values of a dephosphorization degree of melts with the various contents of a chrome are fixed at use of a slag-forming mix (CaC_2 + MAS84C4), the makeups of this mix in order of an abatement of maximal value of a dephosphorization degree settle down in the following sequence (90 percent CaC_2+ 10 percent MAS84C4), (50 percent CaC_2+ 50 percent MAS84C4) and (70 percent CaC_2 +30 percent MAS84C4). Is shown, that the introduction in a slag-forming mix of a metal calcium in makeup of a complex alloy such as MASC allows practically on order to increase a degree of its use