Experimental and numerical evaluation of the flexural properties of stitched foam core sandwich structure

This paper summarizes the results of experimental and numerical studies on the flexural behavior of stitched foam core carbon/epoxy laminate skin sandwich structure. Six types of stitched foam core sandwich beam specimens with different parameters were employed in the three-point bending static tests to study the effect of stitching density and core thickness on flexural properties. Based on Eshelby’s tensor and Mori–Tanaka equivalent model, a new model was proposed to calculate the flexural rigidity of stitched foam core sandwich structure. The analytical results are in excellent agreement with experimental results. The experimental and analytical results show that bending strength increase with the increase of stitching density, but the flexural rigidity decrease with the increase of stitching density; failure load, flexural rigidity and shear rigidity increase with the increase of core thickness.