Thermodynamic study of MnO-SiO2-Al2O3 slag system: Liquidus lines and activities of MnO at 1823 K

Autor: Hae-Geon Lee, Dae-Hee Woo, Youn-Bae Kang
Rok vydání: 2002
Předmět:
Zdroj: Metallurgical and Materials Transactions B. 33:915-920
ISSN: 1543-1916
1073-5615
DOI: 10.1007/s11663-002-0075-5
Popis: The liquid MnO-SiO2-Al2O3 system was studied at 1823 K by equilibrating MnO-SiO2-Al2O3 melts of different compositions with Pt-Mn alloys and an oxygen-bearing gas phase. Liquid compositions for cristobalite saturation were determined at 1823 K. A new liquidus for the cristobalite primary field is proposed. The activity of Mn in the Pt-Mn alloy at 1823 K can be represented by the following equation: $$\ln \gamma _{Mn} = - 9.285(1 - X_{Mn} )^2 - 2.0791$$ The MnO activity was measured in different melt compositions, and MnO isoactivity lines were determined. It was found that the MnO activity is relatively insensitive to the SiO2/Al2O3 ratio, but increases sharply above the MnO mole fraction of 0.5. In the low-MnO-concentration range (α MnO
Databáze: OpenAIRE