Thermodynamic assessment ofevaporation during molten steel testingonboard the International Space Station

Kurzfassung

Evaporation control is a critical facility resource during solidification experiments that limits processingtime and must be tracked to ensure facility health. A thermodynamic analysis was performed on aternary FeCrNi sample processed onboard the International Space Station (ISS) using ESAElectromagnetic Levitation (EML) facility in a microgravity environment. A non-ideal solution-basedmathematical model was applied for the overall sample mass loss prediction during this study. Theoverall sample mass loss prediction is consistent with the post-flight mass loss measurements. Thespecies-specific findings from this study were validated using post-mission SEM-EDX surfaceevaluations by three different facilities. The bulk composition prediction was validated using SEM-EDXand wet chemical analysis. The non-ideal solution model was then applied to predict the compositionof the dust generated during EML testing. The thicknesses of the deposited layer on the EML coil atvarious locations were also calculated using the geometry of the facility and results were validated withnear-real-time dust layer predictions from toxicity tracking software developed by the German SpaceCenter (DLR) Microgravity User Support Center (MUSC).