Permeation Investigation of Carbon Fibre Reinforced Polymer Material for LH2 Storage Thermally Shocked and Mechanically Cycled at Cryogenic Temperature

To achieve the sustainability goals set for the European aviation sector, hydrogen
powered solutions are currently being investigated. Storage solutions are of particular
interest, with liquid hydrogen tanks posing numerous challenges with regard to the struc
tural integrity of materials at cryogenic temperatures, as well as safety issues because of the
high flammability of hydrogen. In this context and in the scope of the Horizon 2020 Clean
Aviation Joint Undertaking (CAJU) project H2ELIOS, the gas permeability behavior of
prepreg tape carbon fibre reinforced polymer (CFRP) material was studied. Investigations
were performed after thermal shock to 20 K (liquid hydrogen immersion) as well as after a
uniaxial stress application at 77 K to identify the shift from Fickian behavior after diverse
aging conditions. Helium gas permeation was tested at room temperature (RT), and its
representativeness to hydrogen permeation in a range of temperatures was considered in
the study. The material’s permeation behavior was compared to ideal Fickian diffusion
as a means of identifying related permeation barrier function degradation. Finally, it was
possible to identify Fickian, near-Fickian, and non-Fickian behaviors and correlate them
with the material’s preconditioning.