@article{98c2a1f699d44de98d769569c1e94a22,
title = "Measurements of density of liquid oxides with an aero-acoustic levitator",
abstract = "Densities of liquid oxide melts with melting temperatures above 2000◦C are required to establish mixing models in the liquid state for thermodynamic modeling and advanced additive manufacturing and laser welding of ceramics. Accurate measurements of molten rare earth oxide density were recently reported from experiments with an electrostatic levitator on board the International Space Station. In this work, we present an approach to terrestrial measurements of density and thermal expansion of liquid oxides from high-speed videography using an aero-acoustic levitator with laser heating and machine vision algorithms. The following density values for liquid oxides at melting temperature were obtained: Y2O3 4.6 ± 0.15; Yb2O3 8.4 ± 0.2; Zr0.9Y0.1O1.95 4.7 ± 0.2; Zr0.95Y0.05O1.975 4.9 ± 0.2; HfO2 8.2 ± 0.3 g/cm3. The accuracy of density and thermal expansion measurements can be improved by employing backlight illumination, spectropyrometry and a multi-emitter acoustic levitator.",
keywords = "Hafnia, Levitation, Melting, Rare earth oxides, Thermodynamics, Zirconia",
author = "Ushakov, {Sergey V.} and Jonas Niessen and Quirinale, {Dante G.} and Robert Prieler and Alexandra Navrotsky and Rainer Telle",
note = "Funding Information: Aerodynamic levitation in a conical nozzle (CNL) [38–41] has been used extensively for oxide melts; however, it has limitations of limited sample visibility and large thermal gradient. The development of an aero-acoustic levitator (AAL) was funded by NSF and NASA and built by Intersonics Inc. in 1990 [42]. In this method, the sample is stabilized above the gas jet by acoustic forces that allow unimpeded access for multi-beam laser heating, pyrometer aiming and video recording. Funding Information: Funding: This research was funded by the U.S. National Science Foundation under the award NSF-DMR 1835848 (changed to NSF-DMR 2015852 on funding moved from UC Davis to ASU). Operation of aero-acoustic levitator at RWTH Aachen is funded by German Research Foundation Grants No Te146/37-2 and No GZ/Inst 222/779-1 FUGG AOBJ:544260. Funding Information: This research was funded by the U.S. National Science Foundation under the award NSFDMR 1835848 (changed to NSF-DMR 2015852 on funding moved from UC Davis to ASU). Operation of aero-acoustic levitator at RWTH Aachen is funded by German Research Foundation Grants No Te146/37-2 and No GZ/Inst 222/779-1 FUGG AOBJ:544260. Publisher Copyright: {\textcopyright} 2021 by the authors. Licensee MDPI, Basel, Switzerland.",
year = "2021",
month = feb,
day = "2",
doi = "10.3390/ma14040822",
language = "English (US)",
volume = "14",
pages = "1--13",
journal = "Materials",
issn = "1996-1944",
publisher = "MDPI AG",
number = "4",
}