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Introduction: The surface of aramid filament is smooth, which is a great defect for impact resistance and composite molding of aramid/epoxy composite. In this study, a new type of yarn—aramid core-spun yarn is introduced to the fabrication of compositematerials. It increases the friction among yarns and optimizes the performance of yarns.Methods: To verify the improvement of yarn in the composite material, the hand lay-up process is used, and the first layer and the fourth layer are replaced by core-spun yarns in a four-layer composite configuration.Results and Discussion: The energy absorption, and the damage of the impacted surface and the back surface are evaluated through the drop weight impact test. The yarn pull-out test can reflect the internal friction of fabric. The results show that the average energy absorption of new yarn in the first layer is 10 J cm2/g more than that in the fourth layer at a 90°/45°/-45°/0° configuration after the normalization, but the conclusion is contrary when the structure is -45°/0°/90°/45°. Under the structure of 90°/45°/-45°/0°, the damaged area of the fabric is larger when the aramid core-spun yarn is laid on the first layer, while a contrary result can be found for the structure of -45°/0°/90°/45°. The fundamental research will provide design ideas and supports for aramid composite.

The impact resistant composite has excellent energy absorption efficiency, but the structure and material selection of the composite have great influence on its energy absorption. In order to explore the effect of structure on the energy absorption of Ultra-high molecular weight polyethylene (UHMWPE) composites and the application potential of new aramid core-spun yarn and new polyester core-spun yarn in impact resistant composites. The UHMWPE composites with different fiber orientations and stacking sequences structure, as well as the new hybrid composites containing aramid core-spun yarn and polyester core-spun yarn were tested by low-velocity impact test and scanning electron microscope (SEM) observation. The differences of energy absorption of UHMWPE composites with different structures and the advantages of the new hybrid composites were analyzed. The results show that the energy absorption of the 45°/0°/90°/−45° UHMWPE composite is 15% and 86% higher than that of the 0°/90°/0°/90°UHMWPE composite and the 0°/90°/45°/−45° UHMWPE composite, respectively, which is the best structure among the three composites. The energy absorption performance of the composites introduced with aramid core-spun yarn and polyester core-spun yarn were improved by 223% and 202%, respectively, so that the energy absorption performance was significantly improved by new yarns.