Flexural behavior of sandwich composite

Abstract

Composite sandwich structures are commonly used in aerospace application, ship building, bridge, etc. due to their low weight and excellent strength to weight ratio. In the last decades, light-weight core materials such as honeycomb, wood, foam core have been used in manufacture sandwich structures based on required. In this case, sandwich structure with poly-propylene honeycomb core and FGRP face sheet was modeled, produced, fabricated and tested. The composite sandwich structures were manufactured using hand lay-up and vacuum bagging manufacturing process. The behaviors of these structures under three point bending and four point bending were investigated. Flexural behavior of these structures has been experimentally and finite element investigated. Design sandwich composite structure with different thickness, manufacturing process and glass fiber skins. The main aim of the study is to analyze effect of material, loading span length, thickness and manufactured process on flexural behavior of the sandwich panel in load rate 1mm/min. The experimental and finite element results were discussed and general conclusions were drawn. The result showed that flexural behavior of the sandwich composite beam with vacuum bagging technique was better than with hand lay-up. The result however indicated that increasing the number of layers decreased the amount of extension, but vacuum bagging method made the value of extension higher, and also in four point bending test, the span length has a significant role in the flexural properties of sandwich composite. By increasing the distance of load span, the number of maximum load obviously went up, but by reducing the span length, the value of flexural extension and maximum stress also had upward trends. The error of maximum stress value in the three-point bending test between the FEM analysis and experimental results declined as it was added to the number of layer and vacuum bagging method process.