Effect of CaF<sub>2</sub> on Viscosity and Refining Ability of Highly Basic Slags for Duplex Stainless Steel

To optimize CaF2 content in highly basic CaO-18%Al2O3-SiO2-10%MgO-CaF2 (%CaO/%SiO2=6, denoted as C/S=6) refining slags used for the production of Al-killed duplex stainless steel with high cleanliness demand, effect on viscosity and ability were studied compared typical CaF2-free CaO-30%Al2O3-SiO2-10%MgO (C/S=6) slag. The addition decreasing slag becomes less obvious increasing temperature content. When exceeds 10%, only marginally decreases further Both monoxide-CaO monoxide-MgO phases are precipitated all CaF2-bearing slags. slightly increases precipitation, but dramatically precipitation. Viscosities also theoretically calculated good agreement measured values was observed. Moreover, 6% has very close viscosities above 1833 K much lower below K, Further evaluation confirms that is sufficient mechanism discussed from viewpoints behaves a network breaker suppresses precipitation solid phases. first aspect identified to play greater role viscosity.