Space Environmental Effects on Multifunctional Radiation Shielding Materials

The two primary material requirements for a crewed habitat or spacecraft to operate beyond low earth orbit (LEO) include effective radiation shielding against the space radiation and secondary neutron environment and sufficient structural and thermal integrity. In this context it is mandatory to study the effect of long duration space environment on any proposed multifunctional radiation shielding material. In this paper we discuss two radiation shielding composite architectures and their long duration performance in LEO. Samples were flown on NASA's The Materials International Space Station Experiment (MISSE) platform and their structural, optical, and radiation shielding capabilities were characterized pre and post flight. Results showed composite architecture can be key in determining expected damage irrespective of sample placement orientation on the space station. A surface layer with a protective or sacrificial coating can be instrumental in minimizing property degradation even when exposed to orientations with high estimated sun hours and high fluence of atomic oxygen.