Effects of MgO content and CaO/Al₂O₃ ratio on surface tension of calcium aluminate refining slag

Abstract

Surface tension of calcium aluminate refining slag was measured by the Slide method at 1823 K. Based on different levels of the MgO content and the mass ratio of CaO to Al₂O₃, the effects of MgO content and the mass ratio of CaO to Al₂O₃ on surface tension were investigated. The results indicate that surface tension decreased with increasing MgO content (from 0 to 4.86%), followed by an increase with further increasing MgO content up to 11.33%. The trend that surface tension changed with the mass ratio of CaO to Al₂O₃ was the same as the trend that surface tension changed with the MgO content. The surface tension was varied from 0.617 N/m to 0.710 N/m, for the mass ratio of CaO to Al₂O₃ varying between 0.60 and 1.28. An attempt was made to estimate surface tension of CaO−Al₂O₃−MgO slag and its sub-system, and the application showed that the model worked well.

Keywords

surface tension / slag / MgO content / mass ratio of CaO to Al₂O₃

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