The Effect of Alumina Nanoparticles Impregnated Kevlar on Ballistic Resistance of Aluminum Alloy 7075 Hybrid Laminate Composite for Armor Application

Military equipment development, especially means of transportation, currently revolves around material selection, which includes hybrid laminate composite as a prominent material choice due to its strength-to-weight ratio. The hybrid laminate composite was fabricated by involving aluminum alloy 7075-T6 sheets and Kevlar fabrics that were introduced to shear thickening fluid (STF). STF was made by mixing PEG-400, alumina nanoparticles, and ethanol in a certain ratio. The composites were fabricated using variations of Kevlar layers of 8, 16, and 24 layers. Ballistic impact resistance of the hybrid laminate composite was observed through a ballistic test that was performed according to the National Institute of Justice (NIJ) 1080.01 level II standard. The energy absorption of the composites was evaluated by analyzing the diameter of the perforation. Additionally, the failure mode of the Al7075 matrix and Kevlar fabric are discussed. The findings from ballistic testing indicated that the addition of alumina nanoparticles into three variations of Kevlar layers in hybrid laminate composite yielded the improvement of ballistic performance and impact energy of the composites.