2020 №01 (06) DOI of Article
2020 №01 (02)

Electrometallurgy Today 2020 #01
SEM, 2020, #1, 8-13 pages

Thermodynamics of interactions and physical properties of slags of 30CaF2/30CaO/30Al2O3 (SiO2, MgO) system at electroslag remelting

L.O. Lisova1, G.P. Stovpchenko2, I.O. Goncharov1, Ia.V. Gusiev1, L.B. Medovar1
1E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
2PC «ELMET-ROLL». P.O. Box 259, 03150, Kyiv, Ukraine. E-mail: office@elmet-roll.com.ua

Thermodynamic calculations of the equilibrium content of components in the gas–slag–metal system were performed for the conditions of electroslag remelting of 15Cr11MoV steel in inert gas atmosphere (argon) under 30CaF2/30CaO/30Al2O3 slags with various SiO2 (1; 2,5; 4 wt.%) and MgO (3; 6; 12 wt.%) content. Appearance of MnO (0.04…0.07 wt.%) and FeO (0.01…0.02 wt.%) oxides in the equilibrium composition of the system indicates a minor oxidizing effect caused by the slag on the metal. The element content in the metal still remains within the margins of standard requirements to 15Cr11MoV steel. According to the results of viscosity and electrical conductivity measurements, a new slag composition has been proposed (ANF-39: 29…35 % CaF2, 30…36 % Al2O3, 27…32 % CaO, 2…4 % MgO, 1…3 % SiO2, TC 20.5-05416923-112: 2015), which has a wider solidification range and lower conductivity than the foreign analogue ESR 2015. The latter is a prerequisite for the reduction electricity consumption during remelting. Ref. 17, Tabl. 2, Fig. 2.
Keywords: electroslag remelting; thermodynamics of gas–slag–metal interaction; viscosity; electrical conductivity; energy-efficient slag

Received 4.02.2020


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