|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Materials Processing Fundamentals
||Effect of BO1.5 Addition on the Thermal Conductivity and the Structure of the CaO-BO1.5-AlO1.5 Mold Flux System
||Sakae Shirayama, Youngjae Kim, Kazuki Morita
|On-Site Speaker (Planned)
Thermal conductivity of the CaO-BO<SUB>1.5</SUB>-AlO<SUB>1.5</SUB> mold flux system was measured at above 1500 K by using transient hot-wire method. Composition dependency of the thermal conductivity of the flux was discussed from the aspect of its local structure analyzed by Raman spectroscopy. Under the fixed CaO/AlO<SUB>1.5</SUB> molar ratio of 1.38, addition of BO<SUB>1.5</SUB> resulted in higher thermal conductivity at first. In this region, an increase in 4-coordinated borate structure was observed and expected to provide a network with aluminate. When the concentration of BO<SUB>1.5</SUB> reached about 55mol%, thermal conductivity decreased along with a decrease in AlB<SUB>3</SUB>O<SUB>7</SUB> structure. From these results, both BO<SUB>1.5</SUB> and AlO<SUB>1.5</SUB> were considered to behave as a network former at the investigated CaO/AlO<SUB>1.5</SUB> ratio. Furthermore, higher acidity of SiO<SUB>2</SUB> than AlO<SUB>1.5</SUB> was confirmed by comparison to the results for the CaO-BO<SUB>1.5</SUB>-SiO<SUB>2</SUB> mold flux system.
||Planned: None Selected