Thermal Conductivity Measurement of Molten Silicon by a Hot-Disk Method in Short-Duration Microgravity Environments

The thermal conductivity of molten silicon was measured by a hot-disk method in short-duration microgravity environments. The hot-disk sensor was made of molybdenum foil cut in a conducting pattern and covered with an aluminum nitride plate. Aluminum nitride has good resistivity against corrosion from silicon melt and the molybdenum foil was protected from the molten silicon. The thermal conductivity of molten silicon measured on the ground was estimated to be 45.6 W·m -1 ·K -1 at the melting point (1687 K). The thermal conductivity of molten silicon measured in microgravity was about 5% lower than that measured on the ground.