An investigation about the reinforcement of composite plates with needle punched nonwoven fabrics produced from polyester resin and glass fiber

In this Thesis, the effect of parameters such as glass fabric, glass mat, core mat, polpropylene and needle felt (PES) type, stacking order and number of layers on the mechanical properties of the composite plates were searched. Composite plates were produced by open molding (hand lay-up) method. Because of that, laboratory scale open molding process was established. Polished stainless-steel plates are used on the lower surface of the plates to produce one face smooth plates. The plates which we produce with open molding method are produced by completing their own curing at 25˚C. As fiber, glass mat with a weight of 450 gr / m², glass fabric with a weight of 500 g / m², PP needle punched nonwoven fabrics with a weight of 100-150-200 gr / m², PES needle punched nonwoven fabrics with weights of 100-150-200 gr / m², weight of 90 g Core SP was used. Resin is IR-100 Polyester suitable for hand lay-up. Eight different stacking and fixed plates were obtained. In the open hand lay-up process, 1-2 times resin circulation was applied to cope with wetting problems depending on the type of layer. The curing is completed on the mold by means of hardener and accelerator reactions without applying heat on the mold after hand lay-up. For the obtained composite plates, basic mechanical properties such as tensile, three-point bending, compression and inter-layer slip were searched. After Resin circulation, wetted layers increased the mechanical properties of the composite plate. Finally, optimum open molding parameters, stacking order and number of layers are recommended.