Engineering Commons^™

Low Temperature Dielectric Strength Of Polyimide-Silica Nanocomposites For Applications In High-Temperature Superconducting Cables, Michael John Mccaffrey

Theses and Dissertations

Gaseous helium is often considered as an alternative to liquid nitrogen to cool modern high-temperature superconducting cables in support of increased power capacity and/or reduction of required cable size. However, the small size of helium molecules and relatively poor dielectric strength of helium gas create challenges which limit the usefulness of modern cable dielectrics. Continuous dielectric coatings have been considered as an alternative to traditional lapped tape dielectrics to support gaseous helium refrigerants, but unmatched thermal contraction between the coating and cable components would induce failures due to mechanical stress. Composite materials have been considered as a means of matching …