At the Princeton University Plasma Physics Laboratory (PPPL), physicists and engineers have designed an experimental apparatus for studying magnetic reconnection, a physical process that drives solar flares, the Northern and Southern Lights, and other dramatic solar events.1 Through the process of magnetic reconnection, magnetic field energy is converted into enormous amounts of thermal and kinetic energy, and high energy charged particles are hurled into space at up to the speed of light.
Among the key components in PPPL’s apparatus, known as the FLARE (Facility for Laboratory Reconnection Experiments) device, are two flux core assemblies. Manufacturing specifications for these assemblies require the use of Master Bond EP29LPSP low outgassing epoxy resin in several steps in the fabrication process. Selected for its low outgassing and cryogenic serviceability properties, EP29LPSP is applied in three distinct ways in the assembly of the flux cores:
- Wet wrap: Fiberglass tape is saturated with EP29LPSP epoxy resin and used to wrap leads together into a bundle and to wrap the inner and outer layers of the toroidal flux cores.
- Epoxy paste: EP29LPSP resin is mixed with a fine silica powder to create an epoxy paste. This paste is then used to secure wires placed in grooves that are cut into the core as well as cables that are threaded through cross-hole regions within the core, preventing motion and potential damage to wires and cables during operation. The paste is also used to secure an aluminum shell to the inner flux core, to fill gaps, and to create a smooth surface in preparation for a vacuum-sealing membrane.
- Coating: A thin uniform coat of EP29LPSP is applied to machined seal grooves in a toroidal G-10 (fiberglass laminate) plate to prepare a smooth surface for sealing support leg o-rings to the plate.