Future International Space Station (ISS) experiments led by Professor Kenneth Kelton aim to answer fundamental questions about nucleation and liquid structure for specific metallic compositions. This talk will first discuss the classical theory of nucleation as well as the coupled-flux model for nucleation. Secondly, the talk will cover liquid structure studies in relation to the nucleation barrier and in relation to other transitions that occur in liquid. These previous sections will serve as background for the discussion of the planned ISS experiments. On the ISS, an electromagnetic levitation (EML) apparatus will be used to measure the maximum undercooling for the carefully selected metallic alloy compositions, and the specific heat, viscosity, density, and electrical resistivity of the undercooled liquids will be measured as well. Lastly, results from ground-based studies on the liquid structure of Zr-Ni and Zr-Pt binary alloys will be presented, highlighting the use of the Washington University beamline electrostatic levitator (WU-BESL) for x-ray diffraction studies and the methods used for analysis and characterization of liquid x-ray data.
Coffee: 4:00 pm, 204 Crow