Fabrication of sandwich panels with glass/vinylester composite face-sheets and polyvinyl chloride (PVC) lattice core using vacuum infusion process for marine applications

In this research, a method based on the vacuum infusion process is proposed for making sandwich panels used in the marine industry. The mechanical properties of the product made with this method have been significantly improved compared to the adhesive bonding method, and also from an economic point of view, it’s cost-effective to use this method. In this method, the construction of face-sheets and their adhesion to the core is done in a single step, which results in some benefits such as reducing construction costs, increasing the production speed and improving the quality of the face-sheets adhesion to the core. According to the intended application, i.e. application in the marine industry, the core is made of grooved Polyvinyl Chloride (PVC) foam and the face-sheets are made of glass/vinylester, which are well-known materials in the marine industry. The mechanical properties of the sandwich panel made by the proposed method have been investigated in both bending and compression loading. The results indicate that in the product made with the proposed method, the bending strength has increased by 78%, the compressive strength has increased by 92%, and the energy absorption has increased by 101% compared to the sandwich panel made by adhesive bonding method. The main factor in improving the mechanical properties of this product is the creation of a network of resin in the empty space of the grooves, which creates a structure similar to the foam filled honeycomb cores and strengthens the core, especially in the thickness direction.