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High-velocity impact resistance of FRP composites consisting of Kevlar, carbon and glass in hybrid and non-hybrid stacking sequences was studied through experimental and finite element analysis. Neat Kevlar/epoxy and Kevlar/glass/epoxy sandwich composites have the 1st and 2nd highest impact energy absorption percentage (100% and 97.99%, respectively). Carbon/epoxy composite exhibited the least energy absorption (38.78%). Other hybrid composites showed intermediate values of energy absorption in the range 38.58%–44.11%. Hybridization did not show any improvement in interlaminar shear strength of composites either. However, hybridizing Kevlar based composites with glass in the middle layer offered impact resistance close to Kevlar/epoxy composite while offering a 21% saving in material cost. Thus, such Kevlar and glass fabric-based sandwich composites possess a great potential as protective structures due to their ability to withstand impacts up to 200 m.s−1 velocity. These composites may also be considered for development of protective armor that are light-weight compared to conventional materials and more affordable. Finite element simulation results are in good agreement with that of experimental results with differences below 14%.

The energy absorption due to low-velocity impact on non-hybrid and hybrid (Kevlar-K, carbon-C, and glass-G) fabric reinforced epoxy composite laminates were studied by conducting standard drop weight tests. The experimental energy absorption results were compared with finite element analysis results. Both values were in good agreement with a maximum variation of about 6%. Kevlar/epoxy (K/K/K) specimen recorded the highest energy absorption (18.67 J) followed by Kevlar specimen sandwiched with glass fabric in the middle layer (K/G/K) (17.24 J). Specimens consisting of glass or carbon layers in the middle, sandwiched by Kevlar layers at the top and bottom (K/G/K and K/C/K) exhibited better energy absorption compared with laminates consisting of all three fabric reinforcements (K/C/G (13.38 J), G/C/K (16.11 J) and C/G/K (16.04 J), respectively). Considering the cost of these composite laminates, K/G/K composite offers 21% reduction in material cost when compared to K/K/K specimen and also offered reasonably enhanced impact resistance and energy absorption as compared to other hybrid composites. Hence, this data may be useful for developing cost effective impact resistant components for defense (protective helmets and body armor) and aerospace (aircraft body components) sectors. The morphological study of the drop weight impact tests revealed that, delamination, fiber breakage, fiber splitting, and matrix cracking are the major damage mechanisms observed in the study. The cost was found to be a critical factor to compare between the different composites.