Thermochimica Acta, Vol.415, No.1-2, 47-54, 2004
Thermophysical properties of solid and liquid platinum
With ohmic pulse heating the measurement of thermophysical data of electrically conducting materials far into the fluid stage are possible. Heating rates up to 10(8) K/s are achieved, and the fluid state is achieved after about 30 mus. Within this short time the geometry of the sample will neither be destroyed through force of gravity, instabilities nor other effects, so that short-term measurements become possible at "standing" fluid columns. The values of heat capacity and enthalpy of platinum in the solid state, obtained by ohmic pulse heating, are complemented with measurements of a differential scanning calorimeter in the temperature range 473-1573 K. Measured data are the current through the sample, the voltage drop across the sample, the radiation temperature and normal spectral emissivity at 684.5 nm. These data are evaluated and one obtains enthalpy, specific heat capacity, electrical resistivity and thermal conductivity as a function of temperature up to 3000 K. (C) 2004 Elsevier B.V. All rights reserved.