Modification of mechanical properties of woven fabric reinforced composites by adding nonwoven fabric

In this study, woven (plain, 300 gsm) and nonwoven (100 gsm and 150 gsm) fabrics made of E-glass fiber were used as layers and interlayers, respectively for the production of composite samples. The woven fabrics (12-layer) and nonwoven fabric (4-6-10-layer) were stacked in cross-layers (90⁰/0⁰) in four different stacking sequences. Polyester matrix E-glass fiber reinforced composites were produced by vacuum infusion technique. The composite sample having no nonwoven interlayers was accepted as reference. The physical (thickness, density and fiber volume fraction) and mechanical (tensile and impact) properties of the composites were determined. Also, tensile test was applied in 90˚ and 0˚ direction. The reference composite sample showed the lowest thickness and the highest density. The thickness of the composites was increased while the density was decreased by the use of nonwoven interlayers and interlayers with higher areal density. The tensile modulus and strength results were comparable for 90˚ and 0˚ directions. The samples including 10 layers nonwoven with 150 gsm areal density showed the lowest tensile modulus and tensile strength in both 90˚ and 0˚ directions. In terms of total impact energy absorption, the composite consisting totally of woven fabric exhibited an obvious superiority compared to the other composites including nonwoven interlayers.