Overview of EP30HT-LO
Master Bond EP30HT-LO is a moderate-viscosity, two-component, epoxy system that can be cured at room temperature, or at elevated temperatures for a faster cure. It can bond to various substrates, including metals, composites, glass, ceramics, and many rubbers and plastics. When cured, it remains rigid without becoming brittle and meets NASA’s low outgassing specifications. In fact, NASA used silver-doped EP30HT-LO to study the effect of gamma radiation on titanium-water thermosyphons that may be used in vehicles for future missions to the moon or Mars.
Application
Fission power systems are being investigated for powering the exploration vehicles used in missions to the moon and Mars. In order for these vehicles to function properly, the heat generated by the fission power systems must be dispersed into the surrounding environment by pipes (i.e., thermosyphons) embedded in radiator panels. Titanium-water thermosyphons spread heat across these radiator panels, but because they are located so close to the reactor, they are exposed to gamma radiation. The radiolytic decomposition of water inside the thermosyphons may produce non-condensable gases that decrease the thermosyphon’s cooling performance.
To investigate the production of non-condensable gases inside the thermosyphons, researchers at NASA Glenn Research Center conducted an accelerated radiation experiment in which thermosyphons were irradiated with the equivalent of 8 years of gamma radiation. As part of their experimental setup, the authors doped EP30HT-LO with silver and then used it to bond titanium thermosyphons to a graphite substrate, as well as graphite/isocyanate composite cooling fins.
To read about the key parameters, requirements, and results, please download the full case study.
Download full case study
Reference
Sanzi, J. L.; Jaworske, D. A.; Goodenow, D. A. Titanium-Water Thermosyphon Gamma Radiation Exposure and Results; 10th International Energy Conversion Engineering Conference (IECEC); Atlanta, GA, 2012.