Hiromichi Ohta, Hiroyuki Shibata, Hiroki Hasegawa, Takaya Kowatari, Yasuhiro Shiroki, Shin-Ya Kitamura, Yoshio Waseda
April 18, 2013
Reliable values of thermal conductivity of molten silicates are strongly requested to establish a model which can describe the relationship between thermal conductivity and structure of the molten silicates. Thermal conductivity of R-Na 2 O-SiO 2 (R = Al 2 O 3 , CaO) molten slags has been measured by using the novel laser flash method. A thin platinum crucible was filled with silicate melt and the bottom surface of the platinum crucible at high temperature was irradiated by a pulsed laser. After irradiation, a temperature decay of the bottom surface of the platinum crucible was measured with an InSb infrared detector. The value of the thermal conductivity was determined by fitting the measured temperature response curve to theoretical one with a least square method. Measured thermal conductivity slightly depends on temperature in molten state with the chemical compositions of the slags presently investigated. On the other hand, the thermal conductivity was found to decrease with increasing NBO/T (Non-Bridging Oxygen ions / Tetrahedrally coordinated cation) values.