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The Design, Construction, and Implementation of an Electrostatic Levitation Facility for Neutron Scattering Studies of Liquids
Date of Award
Doctor of Philosophy (PhD)
The amorphous solid, or "glassy", state is one of the least understood phases of condensed matter, particularly in the context of metals. Insight into the atomic structures and dynamics of equilibrium and supercooled liquids that form glasses can lead to a better understanding of the transition from a liquid to a glass. To mitigate contamination from sample containers due to the high temperature and extreme reactivity of the metallic systems of interest, these experiments must be made in a containerless environment. This project focuses on the construction of a new facility that is capable of making such measurements, to be integrated into the new Spallation Neutron Source located at Oak Ridge National Laboratory. Now complete, it will provide hitherto unseen data on the atomic structures and dynamics in supercooled liquids.
This dissertation will begin with a background of the scientific and practical motivation for undercooled studies of liquid metals, proceed to a description of electrostatic levitation as a method of containerless processing, and explain how electrostatic levitation experiments using neutron scattering can complement similar experiments previously conducted using X-rays.
Neutron scattering experiments are also coupled with a set of challenges unlike that for X-rays, prompting innovations which will be elucidated as the new Neutron Electrostatic Levitator's design is detailed, and considerations about integration with the Spallation Neutron Source's instruments will be discussed. Finally, this dissertation will cover the results of two stages of commissioning at different neutron instruments, and suggest avenues for future research and design improvement.
Kenneth F Kelton
Phillip Gould, Kenneth Jerina, Zohar Nussinov