An experimental study of the fiber hybridization effect on the mechanical performance of the 2D braided tubular composites

This paper presents an experimental investigation of the hybridization impacts on the tensile performance of the two-dimensional (2D) braided tubular composites by varying the types of constituent fibers and combination. Fifteen types of tubular braids with different combinations of three types of yarns-polyester (PET), polypropylene (PP) and polyamide 6 (PA)-were produced on a braiding machine. Subsequently, the vacuum infusion process (VIP) was adopted for the fabrication of hybrid braided composites (HBCs). The hybridization of the yarns with different mechanical properties was carried out so that the influence of the fiber type and ratio on the tensile behavior of the HBCs could be recognized. The mechanical properties (i.e. ultimate tensile strength (UTS), strain at failure, modulus of elasticity and fracture toughness) of HBCs were evaluated, and different types of HBCs were compared against one another to understand the benefits of hybridization and the resulting performance enhancements. Afterward, HBCs with the most satisfying mechanical performance were determined based on the scoring each of the evaluated mechanical parameters. The results indicate that the ternary hybrid composite with a combination of 75% PA-12.5% PET-12.5% PP presents the highest values of tensile performance. Besides, this study reveals that the reinforcement materials and their ratio play a significant role in tensile performance, and also the interaction within each pair of constituent fibers could alter the nature of the final behaviors. Finally, our findings exhibit the existence of positive and negative hybrid effects in UTS, strain at failure, modulus of elasticity and fracture toughness.