Density of gadolinium oxide in its liquid phase was measured using a containerless technique under microgravity environment in the International Space Station (ISS). An electrostatically levitated sample was melted using high power semiconductor lasers. Pictures of a molten spherical sample were analyzed and corresponding volumes were obtained as afunction of temperature. After weighing the returned sample mass, the density of the Gd2O3 was found to be 7240 kg/m3 at its melting temperature (Tm = 2693 K).
It can be very challenging to assess the thermophysical properties of melts at temperatures higher than 2000°C, due to chemical reactions between the molten samples and their containers. To overcome this problem, containerless techniques based on electromagnetic, 1,2 aerodynamic, 3,4 or electrostatic 5 levitation have been developed. In the case of electrostatic levitation, the Coulomb force between a charged sample and surrounding electrodes is used to control the sample position. Following the development of several key technologies necessary for stable sample positioning and scientific observations, [6][7][8][9] the Electrostatic Levitation Furnace (ELF) was installed in the International Space Station (ISS) 10 to allow the analysis of containerless materials under microgravity conditions. Because it is difficult to provide a sufficient charge to the majority of oxides such that these materials will levitate under the standard gravitational force, a microgravity environment provides an ideal opportunity to perform experiments. Thus, a combination of laser heating and thermophysical property measurements has been employed in conjunction with the ISS-ELF to determine the
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.