Damage mechanisms in polymer materials for hydrogen storage under high pressure

In the context of the project ‘HyperStock’, within the PEPR strategy “Hydrogène Décarboné”, we study the damaging of materials (polyamide 11, PA11) used as liners in hyperbar hydrogen tanks. We investigate a specific type of damage/evolution mechanism: nano-cavitation caused by explosive decompression under hydrogen gas. To potentially detect a nano-cavitation process, combined USAXS and in-situ tension are required. The studied samples are lab-scale PA11 samples preliminary submitted to compression-decompression cycles in H2 environment (in collaboration with P’ Institut at ENSMA Poitiers). The effects of pressure, temperature and number of cycles on the nucleation and growth kinetics of nano-cavities are evaluated.