Blast-Resistant Design of Structures

Abstract: Abstract This investigation highlights a hybrid composite for bullet and blast protection. The front face of the hybrid composite was made of silicon carbide (SiC), the middle layer of aluminium (Al) Honeycomb and the back face made of para‐aramid fibre—polyetherketoneketone polymer composite, and fabricated by using high temperature epoxy adhesive. The bullet and blast energy were absorbed essentially due to the material configuration of the hybrid composite. SiC forms a hard face layer with high temperature resistance, which absorbs blast energy, blunt shrapnels and resists high temperature. Al Honeycomb absorbs a large amount of energy by deforming itself, and the back layer of polymer composite stops shrapnels. For ballistic tests, a single layer of SiC was used. For the blast test, four layers of SiC were used. The experimental results of ballistic tests proved that the material has been successful in stopping a 7.62 mm hard steel bullet with a speed of 710 m/s fired from a distance of 10 m, which conforms to NIJ level III+. The modified hybrid composite has been successfully tested to withstand improvised explosive device blasts up to 10 kg TNT with 10% shrapnels, with a standoff distance of 5 m, conforming to Level 4 protection specified in STANAG 4569.