National University of Science and Technology «MISiS» (Moscow, Russia):

Dawood A. D., Post-Graduate, the Chair «Metallurgy of Steel and Ferroalloys», e-mail: adad2000@hotmail.com
Semin A. E., Dr. Eng., Prof., the Chair «Metallurgy of Steel and Ferroalloys», e-mail: asemin2007@yandex.ru
Kotelnikov G. I., Cand. Eng., Ass. Prof., the Chair «Metallurgy of Steel and Ferroalloys», e-mail: gikotelnikov@yandex.ru

In this paper the thermodynamics assessment of dephosphorization of chromium steels by using oxides of rare earth metals is presented. Initial phospho-rus content in the investigated metal was 0.034% (in addition to 0.67% of alumin-ium). The amount of slag mix was 3% of metal mass. The infl uence of the input of rare earth oxides (50% Ce, 30% La, 15% Nd, 8% Pr) on the degree of dephosphorization was studied. It was found out during experiments that improve-ment of dephosphorization process of the melt occurred with increasing the input of rare earth oxides: dephosphorization degree makes 20% if the part of rare earth oxides reaches 40%.

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