Investigation of structural performance of polymer sandwich panels with corrugated cores

Abstract

Aircraft wing structures are strongly required to be stiff in order to withstand newlineaerodynamic forces, while structural flexibility is preferable in morphing wings. This newlinediscrepancy makes it a great challenge to realize the morphing aircraft. Many newlineresearchers found solution for this problem to adopt fiber reinforced plastics (FRP) newlinewhich acts flexible in the chord direction and stiff in the span direction. But FRP has newlinelow resistance against compressive instability in the fiber direction and thus low newlinebending strength. In this direction many researchers propose corrugated-form newlinecomposites as a candidate for morphing wings structure. The significant feature of newlinecorrugated core sandwich structure is its high strength-to-weight ratio. The corrugated newlinecore keeps the face sheets apart and stabilizes them by resisting vertical deformations newlineand also enables the whole structure to act as a single thick plate by virtue of its newlineshearing strength. This second feature imparts outstanding strength to the sandwich newlinestructures extended in this work to shear buckling of sinusoidal plates made of newlinecomposites. Early work on the wrinkling and buckling of sandwich panels can be newlineattributed. Corrugated core sandwich structure can considerably increase wrinkling newlinestrength of uniaxial compression loaded lightweight sandwich structures. The newlinecorrugations may also be used to carry some of the shear load of a sandwich. The newlineobjective of the research work is to study feasibility of the application of corrugated newlinecore sandwich structure in wing structures. newlineThe corrugated core sandwiches of various thicknesses (0.5mm, 0.75mm, 1mm) and newlineshape (sinusoidal, square, and triangular) were fabricated using epoxy and glass fiber newlineby hand layup technique.