Thermochimica Acta, Vol.455, No.1-2, 60-65, 2007
The measurements of thermal diffusivity dependent on temperature for pure metals by the new photothermal displacement configuration
The photothermal displacement method has been known as a useful technique to measure the thermal properties, such as thermal conductivity and thermal diffusivity. However, the previous measurements of thermal properties have been performed only at a room temperature. But these would be not valid for all the temperature range because the different heat transfer mechanism by the phonon and phonon-electron scattering occurs at a high temperature in a microscopic view. In order to obtain the thermal diffusivity of pure metals in correspondence to the temperature increase, the surroundings of the sample should be heated and kept at steady state temperature conditions. Therefore, in this study, the new experimental equipment is designed to satisfy such conditions. And the thermal diffusivities for four kinds of pure metals in the temperature range 300-673 K are measured with high accuracy using the photothermal displacement method. (C) 2007 Elsevier B.V. All rights reserved.
Keywords:photothermal displacement;thermal diffusivity;probe beam deflection;thermoelastic deformation;phase difference