The proposed research will implement microgravity based experiments using the jaxa flight electrostatic levitation furnace (ELF) to achieve precise measurements of the thermophysical properties of…

The proposed research will implement microgravity based experiments using the jaxa flight electrostatic levitation furnace (ELF) to achieve precise measurements of the thermophysical properties of supercooled (also called undercooled) molten metal oxides. The work will include both ground based and flight experiments on liquids formed from aluminum calcium silicon and rare earth element oxide mixtures. These liquids are precursors to high value-added glass materials that are used in photonics lasers optical communications and imaging applications. The outcome of the proposed international research collaboration will be to: (i) measure technologically important thermophysical properties of normal and supercooled liquid metal oxides of interest in connection with production of photonic and optical device materials (II) develop thermophysical property datasets that complement existing atomic structure data on the materials under investigation. Use the resulting data to increase understanding of the nature of fragile liquids and the glass transition and (III) disseminate the new data via publication through NASA's physical sciences informatics system and the materials genome initiative to help accelerate the development of new products. We will investigate the behavior of liquid phase metal oxides as they transform to glass in quiescent diffusion-controlled (i.e. without fluid motion) conditions. This work is needed to optimize photonic and optical device materials to obtain uniform properties and stable performance in applications. Overall the work will advance the broader goals of optimizing computational modeling of materials processes and developing superior materials by design. The flight ELF can achieve pristine molten and supercooled samples. Such samples can be studied using non-contact measurements of temperature volume surface tension and viscosity. Spherical samples CA. 2 MM in diameter suitable for experiments in the flight ELF will be made by laser hearth melting. Prior ground-based work demonstrated that the sample materials can be: (i) levitated using electrostatic methods (II) heated using laser beams and (III) melted without significant evaporation. Proposed ground based work will push the limits of these measurements and help to optimize the methods for analysis for the flight data.