Thermally Conductive Insulators for Conduction-Cooled Superconducting Magnets

Superconducting magnets are essential to high field and high field volume applications because of their low relative power consumption and high stability. However, these magnets must be maintained at extremely cold temperatures, near to absolute zero, typically utilizing scarce and costly liquid helium resources. The primary objective of the Phase I work is to improve the thermal conductivity of magnet electrical insulation to further enable the use of conduction cooling as a means of reducing dependence on scarce liquid helium resources for fusion energy, high energy, physics, and medical imaging applications. Key features of the development effort include improvements in thermal conductivity to improve heat transfer in the magnet winding pack and demonstrating the potential of this approach for enhancing conduction cooling of superconducting magnets. The overall goal of this proposed Phase I program is to address heat transfer in the magnet winding pack through the development of epoxy insulation systems with enhanced cryogenic thermal conductivity. In Phase I, we will build upon prior work developing thermally conductive epoxy resin systems by utilizing blended and surface-functionalized fillers to improve performance. Thermal, electrical, and mechanical performance of the resulting systems will be demonstrated. In addition to benefitting fusion energy and high energy physics applications, the proposed work will benefit several segments of the U.S. economy. These include medical imaging, scientific instruments, transportation, and defense. Specific examples include superconducting magnets for Magnetic Resonance Imaging and Nuclear Magnetic Resonance systems.