Experimental Investigation on Quasi-Static Impact Response of Glass/Epoxy Composite Corrugated Core Sandwich Panels

Composite sandwich structures are vastly utilized in the transportation and aerospace industries as highly effective energy absorbers. This paper aims to study a comparative study on the role of the composite corrugated sheet as a core in sandwich panels under low-velocity loading conditions. In this regard, three types of sandwich structures with different corrugated cores, including three unit cells that have identical mass and mechanical properties, are designed and manufactured. The material system utilized for the face skins and core is woven E-glass/epoxy. Corrugated cores are fabricated using specially designed molds and press techniques and afterward bonded to face sheets for the production of corrugated sandwich panels. In the following, by performing the compression tests on corrugated sandwich panels, the impact response, failure modes, and energy absorption ability for different core shapes are explored. The results reveal that the sandwich panels with the rectangular core have a higher capacity in load carrying and energy absorption than the triangular and arc-shaped cores. It is found that the composite sandwich panels with a rectangular profile increased by 1.14 and 3 times in the SEA compared to the other two types of profiles. It is also observed that the initial mode of failure in these core geometries is buckling of cell walls, and continued loading leads to the fracture of the cell walls (fiber breaking), delamination, and debonding between face sheets and core. The present results provide valuable information on corrugated configurations in the design of sandwich structures and engineering applications.