DESCRIPTION
Accurate values of density, surface tension, and viscosity are crucial for understanding and optimizing high-temperature melt processes, including casting, welding, and additive manufacturing. On Earth, containerless methods are employed to avoid contamination from crucibles. However, even with containerless techniques, measurements are still influenced by gravity, and correction models are necessary to interpret the data accurately.
In a microgravity environment, the influence of gravity-induced deformation is eliminated, allowing more direct and reliable determination of thermophysical properties. Nevertheless, previous space-based measurements often neglected the effects of oxygen dissolution into the bulk and oxygen adsorption at the melt surface, both of which significantly alter the measured values.
Oxygen Analysis for Enhanced Utilization of the ISS-ELF via Surface Tension Measurements (OASIS-ELF) addresses these limitations by conducting experiments on the International Space Station. Using the Electrostatic Levitation Furnace, accurate measurements of density, surface tension, and viscosity are obtained for molten platinum, which is selected as a reference material because it is scarcely affected by oxygen and thus serves as a benchmark for oxygen-free conditions. Additionally, measurements are conducted on molten zirconium, with a focus on quantitatively evaluating the influence of oxygen on its thermophysical properties.
The resulting data provides a benchmark for validating ground-based correction methods, improving the accuracy and reliability of terrestrial measurements. Ultimately, these advances support the optimization of industrial processes such as casting and welding, facilitate the development of new high-performance materials, and contribute to energy efficiency, reduced CO₂ emissions, and sustainable industrial development.
