Prof. Shibata is a full professor at Institute of Multidisciplinary Research for Advanced Materials, Tohoku University in Japan. His reasearch mainly focuses on physicochemical approach to interfacial phenomena and thermophysical properties of inorganic materials at high temperatures for high efficiency materials processing. He is an associate editor of ISIJ International and high temperature materials processing.
Thermophysical properties of silicate melts and glasses
Thermophysical properties, such as thermal conductivity, viscosity and so on of oxides in molten state and glassy state are required to elucidate the metal production processes, such as continuous casting, welding, and solidification and crystalline process for utilization of metallurgical slags. Available thermal transport properties of silicate melts and glasses are very limited because of the experimental difficulties at high temperature, within the best knowledge of the present authors. In order to understand intrinsic properties of oxides, we must understand heat transfer mechanism in both states by considering the effect of addition of cations on framework silicates.
First of all, thermal conductivity should be measured precisely with wide variety of chemical composition of silicates melts concerning the relation between framework silicates and thermal propagation. A laser flash method is recognized as a versatile technique for measuring thermal diffusivity of various materials. This laser flash method was originally developed for measuring thermal diffusivity of solid sample. A front heating-front detection laser flash technique, which we have developed, was used to measure thermal conductivity of molten oxides. The structure of oxides was also evaluated by NMR spectroscopy and synchrotron X-ray total scattering.
The main purpose of the present paper is to introduce the developed techniques and the obtained results for the silicate oxides with wide variety of chemical compositions. Then, the heat transfer mechanism will be discussed concerning the structure of the oxides.