Blast Response and Optimization Design of Polyurea-Coated Auxetic Honeycomb Sandwich Panels

This study systematically investigates the mechanical properties of polyurea-coated auxetic honeycomb sandwich panels under explosive load. First, the dynamic deformation process, deformation/destruction modes, maximum deflection, and energy absorption capacity of structures with different coating methods are studied and compared with uncoated structures. Based on this, the influence of polyurea coating thickness, blast center distance, and explosive mass on the anti-explosion capability of sandwich panels with optimal coating positions is investigated. Finally, performance optimization design of the sandwich panel with optimal coating position is carried out. The results indicate that polyurea coating is beneficial for improving the explosion resistance of sandwich panels, and the back side coated sandwich panel (type B) has the best blast resistance. When other variables of the sandwich panel remain unchanged, increasing the thickness of the polyurea layer may effectively suppress the maximum deflection. Meanwhile, increasing the distance between explosion centers and reducing the mass of explosives can significantly reduce the degree of damage to sandwich panels. Compared with the baseline model, the optimized structure shows a 17.9% reduction in the maximum backside deflection and a 66.1% increase in the specific energy absorption. This research provides a potential new way to enhance the explosion resistance of metal sandwich panels.