Influence of CaO content on viscosity of molten CaO-Al2O3-SiO2 system

• Autorzy: Řeháčková L. , Rosypalová S. , Dudek R. , Dobrovská J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The objective of this work is experimental determination of temperature dependences of viscosity of the molten CaO-Al₂O₃-SiO₂ system and assessment of impact of CaO on the viscosity of this system. Design/methodology/approach: The ternary oxide system CaO-Al₂O₃-SiO₂, which represents a simplified basis of the casting powder, was chosen for the experiment. Dependencies of viscosity on the concentration of CaO and on the temperature were determined experimentally. For this purpose were prepared a concentration series with additions of 3, 6, 9, 12 and 15 wt.% of calcium oxide. Experimental measurements of viscosity was performed with use of the high-temperature viscometer Anton Paar FRS 1600. Findings: Viscosity of the studied systems decreases exponentially with the increasing temperature. Viscosity decreases with the increasing addition of CaO. Viscosity reaches its minimum value of 0.447 Pa.s (at T = 1723 K) at the basicity of CaO/SiO₂ = 1.13. Viscosity increases with the further addition of CaO (CaO/SiO₂ > 1.2). Influence of addition of CaO is more pronounced at higher temperatures. Research limitations/implications: Viscosity in molten oxide system is determined by the internal structure. Exact clarification of the change of structure of the oxide system caused by the increased content of CaO requires additional analyses, such as Fourier transformation infrared spectra and Raman spectra. Practical implications: The choice of an optimum slag mode influences not only the main metallurgical processes, but also the values of technical-economic indicators of the whole steelmaking process. Viscosity is an important factor affecting the service properties of slags, as it plays an important role in the area of mass transfer at chemical reactions in metallurgical processes. Originality/value: The viscosities of CaO-Al2O3-SiO2 system were measured under conditions of CaO/SiO₂ = 0.78-1.44, 47.20-35.98 wt.% SiO2, 36.90-51.90 wt.% CaO and 15.90-12.12 wt.% Al₂O₃.

Słowa kluczowe

EN

viscosity; basicity; CaO-Al2O3-SiO2 system; slag

PL

lepkość; zasadowość; układ CaO-Al2O3-SiO2; żużel

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2013
• Tom: Vol. 59, nr 2
• Strony: 61--68
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Řeháčková L.

• Faculty of Metallurgy and Materials Engineering, VSB - Technical University of Ostrava, 17. listopadu 15, 70833, Czech Republic

autor

Rosypalová S.

• Faculty of Metallurgy and Materials Engineering, VSB - Technical University of Ostrava, 17. listopadu 15, 70833, Czech Republic

autor

Dudek R.

• Faculty of Metallurgy and Materials Engineering, VSB - Technical University of Ostrava, 17. listopadu 15, 70833, Czech Republic

autor

Dobrovská J.

• Faculty of Metallurgy and Materials Engineering, VSB - Technical University of Ostrava, 17. listopadu 15, 70833, Czech Republic

Bibliografia

• [1] S. Rosypalová, R. Dudek, J. Dobrovská: Influence of SiO2 on interfacial tension between oxide system and steel, Proceedings of 21th International Metallurgical and Materials Conference, Ostrava, 2012, 109-114.
• [2] M. Žaludová, Experimental study of Fe-C-O based system above 1000°C, Journal of Thermal Analysis and Calorimetry, 112 (2013) 465-471.
• [3] B. Smetana, Application of high temperature DTA to micro-alloyed steels, Metallurgy 51 (2012) 121-124.
• [4] D. Mudersbach, Viscosity of slags, Steel Research 72 (2001) 86-90.
• [5] T. Matsushita, M. Hayashi, S. Seetharman, Termochemical and termophysical property measurement in slag systems. International Journal of Materials and Product Technology 22 (2005) 351-390.
• [6] Slag Atlas, 2nd edition, Verein Deutscher Eisenhüttenleute (VDEh), Düsseldorf, 1955.
• [7] M. Nakamoto, J. Lee, T. Tanaka, A model for estimating of viscosity of molten silicate slag, ISIJ International 45 (2005) 651-656.
• [8] H. Kim, A study on the effect of Na2O on the viscosity for ironmaking slag, Steel Research 81 (2010) 17-24.
• [9] I. Soho, D. J. Min: A review of the relationship between viscosity and structure of calcium - silicate - based slags in ironmaking, Steel Research 83 (2012) 611-630.
• [10] G.H. Kim, I. Sohn, Effect of Al2O3 on the viscosity and structure of calcium silicate-based melts containing Na2O and CaF2, Journal of Non-Crystalline Solids 358 (2012) 1530-1537.
• [11] J. Liao, Effect of Al2O3/SiO2 ration on the viscosity and structure of slags, ISIJ International 52 (2012) 753-758.
• [12] S. Mudry, V. Sklyarchuk, A. Yakymovych, Influence of doping with Ni on viscosity of liquid Al, Journal of Physical Studies 12 (2008) 1601.
• [13] S. Mudry, Viscosity of Sb - Sn melts, Inorganic Materials 46 (2010) 833-835.
• [14] M. Kehr, W. Hoyer, I. Egry, A new high - temperature oscillating cup viscometer, International Journal of Thermophysics 28 (2007) 1017-1025.
• [15] N. Saito, Viscosity of blast furnace type slags. Metallurgical and Materials Transaction B 34 (2003) 509-516.
• [16] B. Vidacak, D. Sichen, S. Seetharaman, An experimental study of the viscosities of Al2O3-CaO-FeO slags. Metallurgical and Materials Transaction B 32 (2001) 679-684.
• [17] A. Ledzki, Dynamic viscosity of blast furnace primary and final slag with titanium and alkali admixtures, Archives of Metallurgy and Materials 54 (2009) 499-509.
• [18] Y.S. Lee, Viscous behaviour of CaO-SiO2-Al2O3-MgO-FeO slag, Proceeding of the 7th International Conference on Molten Slags Fuxes and Salts, The South African Institute of Mining and Metallurgy, 2004, 225-230.
• [19] J.S. Machin, T. B. Yee, D. C. Hanna, Viscosity studies of system CaO-MgO-Al2O3-SiO2:III,35,45 and 50%SiO2, Journal of the American Ceramic Society 35 (1952) 322-25.
• [20] R. Dudek, Possibilities of investigation of viscosity of metallic and oxide melts. metallurgical engineering news 64 (2011) 90-95.
• [21] S. Rosypalová, Influence of temperature and SiO2 concentration on viscosity of molten oxide systems. Metallurgical Engineering News 65 (2012) 15-19.
• [22] K.C. Mills, The influence of structure on the physico-chemical properties of slags, ISIJ International 33 (1993) 148-155.
• [23] V.P. Smoljarenko, A.M. Jakušev, Jedněral, F.P. IVUZ. Čer. Met. 55 (1965).
• [24] F.A. Cotton, G. Wilkinson, Advanced Inorganic Chemistry, New York, 1988.
• [25] E.T. Turgdogan, Physicochemical properties of molten slags and glasses, London, The Metals Society, 1983.
• [26] G. Urbain, Y. Bottinga, P. Richet, Viscosity of liquid silica, silicates and alumino-silicates, Geochimica Cosmochimica Acta 46 (1982) 1061-107.