A PHASE DIAGRAM OF THE FeO–SrO–BaO SYSTEM
DOI:
https://doi.org/10.14529/met200301Keywords:
FeO–SrO–BaO system, thermodynamic modeling, phase equilibria, phase diagramsAbstract
At present, the refinement technology using ligatures containing alkaline earth metals, in particular barium and strontium, is being increasingly introduced into the production of steels and alloys. The construction of a phase diagram of the FeO–SrO–BaO system is of interest from the point of view of the analysis of phase equilibria realized in an oxide system conjugated to a molten metal. In the course of this work, thermodynamic modeling of phase equilibria was carried out, followed by calculation of the coordinates of the liquidus and solidus lines for phase diagrams of the FeO–SrO, FeO–BaO, and SrO–BaO oxide systems. Using the obtained data on binary oxide systems, we performed thermodynamic modeling of phase equilibria with the subsequent construction of a projection of the liquidus surface for the phase diagram of the ternary oxide system FeO–SrO–BaO. For each of the systems, the energy parameters of the theory of subregular ionic solutions, which describes the activities of the components of the oxide melt, were determined. The energy parameter of the theory of regular ionic solutions, which describes the activities of the components of the solid solution of oxides |SrO, BaO|s.s, was also determined. The phase diagrams of the FeO–SrO and FeO–BaO systems are eutectic type diagrams with one eutectic point with coordinates of 18.00 mol. % SrO and 1060 °C; 31.58 mol. % BaO and 1066 °C, respectively. The SrO–BaO system is characterized by unlimited solubility of the components, both in the liquid and in the solid state. For the phase diagram of the FeO–SrO–BaO system, an extensive equilibrium region of the oxide melt with the solid solution of oxides |SrO, BaO|s.s, was noted.At present, the refinement technology using ligatures containing alkaline earth metals, in particular barium and strontium, is being increasingly introduced into the production of steels and alloys. The construction of a phase diagram of the FeO–SrO–BaO system is of interest from the point of view of the analysis of phase equilibria realized in an oxide system conjugated to a molten metal. In the course of this work, thermodynamic modeling of phase equilibria was carried out, followed by calculation of the coordinates of the liquidus and solidus lines for phase diagrams of the FeO–SrO, FeO–BaO, and SrO–BaO oxide systems. Using the obtained data on binary oxide systems, we performed thermodynamic modeling of phase equilibria with the subsequent construction of a projection of the liquidus surface for the phase diagram of the ternary oxide system FeO–SrO–BaO. For each of the systems, the energy parameters of the theory of subregular ionic solutions, which describes the activities of the components of the oxide melt, were determined. The energy parameter of the theory of regular ionic solutions, which describes the activities of the components of the solid solution of oxides |SrO, BaO|s.s, was also determined. The phase diagrams of the FeO–SrO and FeO–BaO systems are eutectic type diagrams with one eutectic point with coordinates of 18.00 mol. % SrO and 1060 °C; 31.58 mol. % BaO and 1066 °C, respectively. The SrO–BaO system is characterized by unlimited solubility of the components, both in the liquid and in the solid state. For the phase diagram of the FeO–SrO–BaO system, an extensive equilibrium region of the oxide melt with the solid solution of oxides |SrO, BaO|s.s, was noted.References
Skok Yu.Ya. Study of the Deoxidizing Ability of Complex Alloys Containing Alkali-Earth and Rare-Earth Metals. Casting Processes, 2010, no. 3 (81), pp. 8–12. (in Russ.)
Grigorovich K.V., Demin K.Yu., Arsenkin A.M., Garber A.K. Prospects of the Application of Barium-Bearing Master Alloys for the Deoxidation and Modification of a Railroad Metal. Russian Metallurgy (Metally), 2011, vol. 2011, no. 9, pp. 912–920. DOI: 10.1134/S0036029511090126
Mikhaylov G.G., Makrovets L.A., Vydrin D.A. Barium as Deoxidant and Modifier of Liquid Steel. Bulletin of the South Ural State University. Ser. Metallurgy, 2013, vol. 13, no. 1, pp. 45–50. (in Russ.)
Ryabchikov I.V., Mizin V.G., Usmanov R.G., Golubtsov V.A., Milyuts V.G. Assessing the Quality of Reducing and Modifying Agents for Steel. Steel in Translation, 2015, vol. 45, no. 2, pp. 137–140. DOI: 10.3103/S0967091215020138
Rozhikhina I.D., Nokhrina O.I., Dmitrienko V.I., Platonov M.A. Modification of Steel with Barium and Strontium. Steel in Translation, 2015, vol. 45, no. 12, pp. 908–912. DOI: 10.3103/S0967091215120104
Provorova I.B., Rozenberg E.V., Baranowski K.E., Volosatikov V.I., Rozum V.A., Karas’ A.N., Chernyavski M.S. The Foundry Inoculant Containing Alkali-Earth Metal for Ladle Refining. Foundry Production and Metallurgy, 2016, no. 2 (83), pp. 14–18. (in Russ.)
Bakin I.V., Shaburova N.A., Ryabchikov I.V., Mizin V.G., Belov B.F., Mikhailov G.G., Senin A.V. Experimental Study of Refining and Modification of Steel with Si–Ca, Si–Sr, and Si–Ba Alloys. Steel in Translation, 2019, vol. 49, no. 8, pp. 543–547. DOI: 10.3103/S0967091219080023
Mikhailov G.G., Makrovets L.A., Samoilova O.V., Bakin I.V. Thermodynamic Analysis of Deoxidizing Ability of Strontium in Liquid Iron: Phase Stability Diagram in Fe–Sr–O and Fe–Mg–Sr–O Systems. Ferrous Metallurgy. Bulletin of Scientific, Technical and Economic Information, 2019, vol. 75, no. 12, pp. 1366–1373. (in Russ.) DOI: 10.32339/0135-5910-2019-12-1366-1372
Samoylova O.V., Makrovets L.A., Bakin I.V. Thermodynamic Simulation of Phase Equilibria in Oxide System FeO–SrO–SiO2. Bulletin of the South Ural State University. Ser. Metallurgy, 2019, vol. 19, no. 4, pp. 10–18. (in Russ.) DOI: 10.14529/met190402
Mikhailov G.G., Leonovich B.I., Kuznetsov YU.S. Termodinamika metallurgicheskikh protsessov i sistem [Thermodynamics of Metallurgical Processes and Systems]. Moscow, MISIS Publ., 2009, 520 p. (in Russ.)
Kubaschewski O., Alcock C.B. Metallurgical Thermochemistry. Oxford, Pergamon Press Ltd Publ., 1979, 392 p.
Darken L.S., Gurry R.W. The System Iron–Oxygen. II. Equilibrium and Thermodynamics of Liquid Oxide and Other Phases. Journal of the American Chemical Society, 1946, vol. 68, pp. 798–816.
Irgashov X., Tarasov V.D., Chekhovskoy V.Ya. Thermodynamic Properties of Strontium Oxide in Solid and Liquid Phases. High Temperature, 1985, vol. 23, no. 1, pp. 86–91. (in Russ.)
Samsonov G.V. Fiziko-khimicheskie svoistva okislov [Physico-Chemical Properties of Oxides]. Moscow, Metallurgiya Publ., 1969, 456 p. (in Russ.)
Revzin B., Pelleg J. Model Evaluations of Phase Diagrams of the Systems SrO–(Mn, Fe, Co, Ni)O. Materials Research Society Symposium Proceedings, 1996, vol. 398, pp. 649–654.
Jacob K.T., Varghese V. Solid-State Miscibility Gap and Thermodynamics of the System BaO–SrO. Journal of Materials Chemistry, 1995, vol. 5, no. 7, pp. 1059–1062.
Van der Kemp W.J.M., Blok J.G., Van der Linde P.R., Oonk H.A.J., Schuijff A., Verdonk M.L. Binary Alkaline Earth Oxide Mixtures: Estimation of the Excess Thermodynamic Properties and Calculation of the Phase Diagrams. Calphad, 1994, vol. 18, no. 3, pp. 255–267. DOI: 10.1016/0364-5916(94)90032-9
Zhang R., Mao H., Taskinen P. Thermodynamic Descriptions of the BaO–CaO, BaO–SrO, BaO–SiO2 and SrO–SiO2 Systems. Calphad, 2016, vol. 54, pp. 107–116. DOI: 10.1016/j.calphad.2016.06.009
