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In past studies, some of the authors presented how the integration of different systems, for the prevention of fires or explosions due to impact or bullet damage, may significantly improve the safety of fuel tanks. Leakage, after bullet penetration or debris impact, can be significantly reduced by introducing polymeric materials with self-healing capabilities for the container’s walls, while an internal aluminium filler can reduce the sloshing and the danger of fuel ignition. In the present paper, an experimental evaluation of the proposed solution is presented. A ballistic test campaign on a fluid container was performed to investigate the interaction between an ethylene–methacrylic acid (EMAA)-based ionomeric wall (i.e. Dupont®Surlyn 8940) and an internal aluminium filler (i.e. Explosafe®). Results show that the presence of the fluid increases the self-healing capabilities, which are however slightly affected by the internal aluminium filler; the contribution in terms of sloshing reduction remains relevant. Moreover, additional configurations based on multilayer panels are presented. The authors studied the healing process of EMAA in a sandwich configuration made of one skin of ionomer and one skin of carbon fibre, sepa- rated by an aramidic honeycomb. The main objective of the honeycomb is to prevent the remarkable reduction of the healing capabilities observed when ionomer is directly coupled to aramidic fabric or composite panels. The new multilayer configurations have been tested at different impact conditions.
fillers, fuel tanks, impact, self-healing
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