Thermal diffusivity measurements of oxide and metallic melts at high temperature by the laser flash method

Abstract

An attempt has been made to describe the current status on thermal diffusivity measurement of oxide and metallic melts by the laser flash method in the temperature range between 1000 and 2000 K. This paper is to provide the principle and the new data processing for the laser-flash methods, including some selected examples of their application in determining thermal diffusivity of oxide and metallic melts at high temperature. To overcome experimental difficulties at high temperature, a differential scheme without information of the absolute value of sample thickness was used in the oxide melt case with the help of a numerical technique to estimate the effect of radiative heat transfer in the cell system where the absorption and emission behavior of the radiative component in the sample layer were considered. For metallic melts, a new simple cell system was developed to keep a precise value of sample thickness and the effect of conductive or radiative heat leak from sample was also taken into account.