Theoretical and experimental investigation of sandwich panels with 3D printed cores with GFRP composite and aluminum face sheets under 3-point bending

Composite structures have been widely used in recent years in the aerospace industry as well as in industries that require lightweight structures due to their lightness and high strength-to-weight ratio. The purpose of this research is to introduce and compare a new type of sandwich panel to introduce structures that can be used in the aerospace industry. The cores in this research are made using Fused Deposition Modeling (FDM) with two types of PLA and ABS polymers. The face sheets used for this study are glass fiber reinforced composites and aluminum face sheets. In the first part of this study, a theoretical model for obtaining the force-displacement curve in nuclei with rectangular geometry was presented. Comparison of theoretical and experimental results showed that theoretical relationships have a good ability to predict the amount of force in experimental tests. The results obtained in this study showed that the use of composites made of epoxy glass fibers as a face sheet for sandwich panels leads to higher resistance to three-point bending. It was also found that sandwich panels made with ABS cores have higher strength compared to PLA cores, but their softness is less.