Influence of Slag Composition on Slag–Iron Interfacial Tension

Abstract

Interfacial tensions between liquid iron and slag were examined for CaO-SiO 2 binary and CaO-SiO 2 -Al 2 O 3 ternary slag systems. The influences of FeO, MgO, B 2 O 3 , TiO 2 , BaO and ZrO 2 in slag on the interfacial tension were also investigated by varying these oxides from 1-30 wt% in the CaO-SiO 2 binary or CaO-SiO 2 -Al 2 O 3 ternary slag systems.The interfacial tensions were determined by the sessile drop technique under argon atmosphere at 1 853 K. An X-Ray radiographic technique was employed to image the profile of molten iron drop in a slag bath and the interfacial tensions between slag and iron were obtained from the drop shape analysis.In examining the effect of slag composition on the interfacial tension, the oxygen in liquid iron and its impact on the interfacial tension was taken into consideration. The interfacial tension was found slightly increased with increasing CaO/SiO 2 ratio in CaO-SiO 2 slag, and with increasing MgO content in the slag. A decrease of interfacial tension was found with increasing FeO in slag. Only minor changes in the interfacial tension were observed with varying the slag composition in the CaO-SiO 2 -Al 2 O 3 ternary slag system and the influences of B 2 O 3 , TiO 2 , BaO, and ZrO 2 in slag on the interfacial tension were found insignificant.

Surface kinetics of nitrogen dissolution and its correlation to the slag structure in the CaO―SiO2, CaO―Al2O3, and CaO―SiO2―Al2O3 slag system

“…This effect of free oxygen ions on the slag surface is also supported by the interfacial tension data of Bretonnet et al [24] in the CaO-Al 2 O 3 binary slag system and Sun et al [25] in the CaO-SiO 2 -Al 2 O 3 ternary slag system shown in Figs. 13 and 14, respectively.…”

Phase field modelling of the attachment of metallic droplets to solid particles in liquid slags: Influence of interfacial energies and slag supersaturation

“…According to literature [17,18], γ LO,LM is of the order of 1 N/m. Furthermore, the interfaces should at least contain five grid points for a sufficient resolution of the diffuse transition at interfaces and to reproduce accurately the surface energies [19].…”

Interfacial Reactions between Slag and Melt in the New World of High Manganese Steels

“…The formation of solid phases in slag increases the viscosity at process temperature, which leads to slow down the transfer of reactants and products near the slag/metal interface [14][15]. On the other hand, some researchers assume that the formation of solid spinel phases decrease the slag/metal interfacial tension, which results finally an increase in interfacial reaction kinetics [8,21]. The several SEM images from slag samples confirm the presence of spinel phases, the bright large angular particles, which are marked by circles on Figure 5(b).…”

“…The melting time was approximately 90 minutes. After the Armco-iron has been melted down under Ar gas atmosphere at 600 mbar, the electrolytic manganese (17)(18)(19)(20)(21)(22) wt.-%) was added to the melt. The chemical composition of Armco-iron and electrolytic manganese are listed in Table 1.…”

“…During the oxygen refining of high manganese molten steel in EAF the manganese content decreases strongly by oxidation and vaporization, which is affected by slag composition, slag properties such as basicity and viscosity, slag weight as well as melt temperature [6][7][8]. This paper is investigating on the interface phenomena and interfacial reaction kinetic between slag and molten steel containing Mn (17)(18)(19)(20)(21)(22) wt.-%) and up to 3 wt.-% Al during melting and refining of high Mn and Al alloyed steels. The effect of changes in the composition of slag and steel on the interfacial reaction kinetics will be studied.…”