Density of molten oxides measured in an aero-acoustic levitator
Year: 2024
Type: article
Abstract: Knowing the thermophysical properties of high-temperature melts can aid the design of melt processes and validate atomic structural models, such as those used in studying glass formation. Property measurements on such melts are challenging, however, due to container-related contamination and heterogeneous nucleation. Containerless processing techniques that employ levitation can be used to avoid these obstacles. In that context, we demonstrate here the application of silhouette imaging to measure the density of molten oxides in an aero-acoustic levitation instrument (AAL). The AAL combines gas jet levitation with actively controlled acoustic positioning to enable full optical access to samples ca. 2–4 mm in diameter, which are laser beam heated and melted. The cross sections of molten drops are imaged using a monochromatic light source and narrowband-filtered camera. Melt volume is calculated from the cross sections and used to find density at several temperatures ranging 1530–1920 K, including up to 350 K of supercooling. We report densities for CaAl2O4, Ca12Al14O33, CaSiO3, their Fe2O3-bearing analogs, and 83TiO2-17RE2O3 (RE = La or Nd). These provide important benchmarks of the capabilities, measurement uncertainties, and future outlook for this technique.
Source: Journal of Applied Physics
DOI: 10.1063/5.0245875
Institution: Materials Development (United States)
Language: English
Subfield: Ceramics and Composites
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,500
Awards: G3830162158, EXTREME TEMPERATURE SAMPLE ENVIRONMENT FOR MATERIALS RESEARCH USING NEUTRON SCATTERING, 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 GROUNDBASED WORK WILL PUSH THE LIMITS OF THESE MEASUREMENTS AND HELP TO OPTIMIZE THE METHODS FOR ANALYSIS FOR THE FLIGHT DATA.
OpenAlex ID: W4405419394