Fiber-reinforced materials are widely used in many industrial applications including civil engineering, automotives, marine, aviation, etc. This is due to their high strength to weight ratios compared to metal structures. One of the major applications of composites is the structural components for automotives such as bumpers, fenders, hoods, door panels. For such applications, impact strength is required since it is directly related to the passenger safety requirements. Sandwich structures are extensively used in automobiles; the understanding of their behaviors under impact conditions is extremely important for the design and manufacturing of these engineering structures. In this study, 27 types of woven fabrics were produced using polyester fibers as warp threads with different structure parameters such as weft yarn material, picks densities, and weaving structures to be used as skin layers and nonwoven fabric was used as core layer. The sandwich composite specimens were prepared using the said woven fabrics with two types of thermoset resins and fabricated via the hand lay up method. The impact properties of the sandwich specimens produced were evaluated to choose the best samples performance to be used in automotive applications. It was found that the impact properties are strongly affected by woven fabric structure parameters and the resin properties.

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Hybrid composites are being growingly utilized in engineering applications, and their mechanical performance is a matter of concern with the employing of various types of reinforcements and matrices. In this paper, an experimental study was performed to characterize the tensile behaviour of new hybrid sandwich composites. The sandwich composites were prepared using reinforcements from woven fabrics for the skin layers and nonwoven fabric for the core layer and two types of matrices; polyester and epoxy resins. The tensile strength of the hybrid sandwich composites produced was examined in both warp and weft directions of fabrics. A particular interest was devoted to the influence of woven fabrics (skins) constructional parameters and the matrix properties on the tensile strength of these hybrid sandwich composites. The results indicated that, the hybrid sandwich composites exhibited high tensile strength in the weft direction of fabrics. The polyester/glass sandwich composites fabricated with epoxy matrix showed the highest tensile strength compared to the other composites. Hence, the reinforcement materials properties and the fiber/matrix interface are greatly affected on the behaviour of the sandwich composites towards tensile loads.