Abstract
Fe-C, Fe-Cr-C and Fe-Mn-C melts were treated with CaC2-CaF2 flux by using a rotating MgO crucible containing 1kg metal at 1 550-1600°C under Ar atmosphere. The important factors of dephosphorization and desulfurization of metal with decomposition reaction of CaC2 were studied.
The degree of dephosphorization, ηP, strongly depended on carbon activity of initial metal, a[C]0, and ηP increased with the decrease of a[C]0, and as a result carbon content in metal increased.
The value of ηs/fs increased with the decrease of a[C]0, where, ηs the degree of desulfurization and fs is activity coefficient of sulfur in metal.
The distribution ratio of phosphorus, LP=(%P)/a[P], depended on calcium content in slag or on a[C]0·LP increased with the increase of (%Ca), and with the decrease of a[C]. The decomposition reaction of CaC2 followed the relationship of NCaC2/NCa=k·a2[C] 20min after flux addition.
CaC2-CaF2 mixture was more effective than only CaC2 flux for dephosphorization of metal.
