Effect of Na_2O additions on thermal conductivities of CaO-SiO_2 slags

摘要

Thermal conductivities of Na_2O-CaO-SiO_2 slags have been determined using the non-stationary hot wire method over a wide temperature range between room temperature and 1773 K, to propose a prediction equation for the thermal conductivities of this slag system. Samples used were xNa_2O-yCa0-zSiO_2 (x + y + z=100 mol-percent), where 50.9 are not dependent upon the (percent Na_2O)/(percent CaO) ratio as long as the SiO_2 concentration is kept constant. This finding indicates that in this system the relationship between thermal conductivities at T_L and NBO/T also applies at temperatures other than T_L using the temperature scale of T/T_L. On the basis of this relationship, the following prediction equation has been proposed for thermal conductivities lambda of this slag system in liquid and supercooled liquid states: lambda=a[1/(T/T_L)] + b, where a and b are constants specified by the concentration of SiO_2. This equation applies, for example, in the temperature range 0.9