NOUVELLE TECHNIQUE DE MESURES DE LA CONDUCTIVITE THERMIQUE ET DE LA CAPACITE CALORIFIQUE DU NICKEL PAR LA LEVITATION ELECTROMAGNETIQUE

Electromagnetic levitation of metals is a technique for measuring their thermophysical properties such as density, heat capacity, thermal conductivity, viscosity, surface tension, etc. Experiments conducted in microgravity on liquid loads are very costly and require a very long time. A new measurement technique has been implemented in the Materials and Process Science and Engineering Laboratory in Grenoble in collaboration with the Neel Institute in Grenoble. This involves an electromagnetic levitator placed in a continuous magnetic field. To ultimately reduce costs while maintaining or even improving the quality of the measurements, we replaced microgravity with a continuous magnetic field, which will reduce electromagnetic mixing within the levitated liquid load. We conducted experiments using the modulated calorimetry process, during which we measured and then recorded temperatures, currents, and frequencies as a function of time in a data acquisition software program called LabView. Using a data processing protocol written in Matlab software, we were able to determine the heat capacity and thermal conductivity of nickel in the solid and liquid states. We then compared the experimental results with data from the literature. This allowed us to validate the measurement processing protocol. Keywords: Electromagnetic levitation, modulation calorimetry, heat capacity, thermal conductivity.