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• Advantages of asymmetric hybridization on impact resistance and resilience. • Rules of external damage area and internal crack volume distribution. • Damage mechanism of carbon/Kevlar hybridization laminates. The ply structure has a significant effect on the impact resistance and failure behavior of composite laminates. In this paper, carbon/Kevlar hybrid fabric reinforcements were prepared with different Kevlar ratio (0%, 25%, 50%, 75%, 100%) by replacing carbon fabric plies on the non-impact side by Kevlar plies. The low-velocity impact tests for all configurations were carried out under 15 J and 25 J energy respectively. The results show that the maximum deflection, impact duration, impact absorption energy and absorption energy efficiency of hybrid laminates increased with the Kevlar hybrid ratio, whereas the peak force presented a decreasing trend, which indicates that the adding of Kevlar layer makes the laminates more ductile than non-hybrid carbon structure. The damage mechanism of the carbon fiber ply was brittle fiber fracture, resin cracking and resin shedding, while the fibers pull-out and tows splitting was found in Kevlar ply. The critical structural damages start from the non-impact side and evolve to the impact side. And the rules of internal crack volume distribution with Kevlar plies are consistent with the trend of external damage area on the non-impact side. It is suggested that in order to take into account the peak strength and excellent structural resilience, Kevlar asymmetric-hybrid ratio of 25% is the most appropriate. The reason is that an appropriate small ratio of Kevlar cushion ply can not only effectively avoid the tensile fracture at non-impact side happened in the non-hybrid carbon structure, but also withstand enough impact load by maintaining a high carbon fiber content. [ABSTRACT FROM AUTHOR]

• The structural hybridization effect on low-velocity impact response of braided/unidirectional (UD) laminates was investigates. • Continuum shell finite element models based on the anisotropic constitutive relationship of braided and UD plies were established to reveal the damage onset and propagation. • The extensive delamination formed rapidly when impacted on the fabric side. • The damage characterized by severe fiber breakage occurs at the impact site when impacted on UD ply side. This work investigated the structural hybridization effect on the low-velocity impact response of braided/unidirectional(UD) laminate. Two groups of hybridization laminates, namely interleaving and clustering groups, were manufactured. The impact performance of the specimens was characterized by combining dropping testbench, optical camera and ultra-sound detector. A continuum shell finite element model was established to reveal the progressive damage behavior of hybridization laminate. The specimen in the interleaving group presented overwhelming performance than that in the clustering group. The impact side effect on failure modes was discussed in detail. When impacted on the braided fabric side, extensive delamination formed on the edge of the specimen due to bending deformation. It further resulted in-plane crushing failure of UD sub-laminate. In contrast, severe fiber breakage occurs at the impact site due to combination stress of tensile and shear when impacted on UD side. Therefore, the fabric-impacted specimen exhibits better impact resistance than that impacted on UD side with respect to higher peak load and lower absorbed energy. [Display omitted] [ABSTRACT FROM AUTHOR]