Study on aluminum honeycomb sandwich panels with random skin/core weld defects

Effects of random skin/core weld defects on out-of-plane tensile, compressive and in-plane shear behaviors of hexagonal cell aluminum honeycomb sandwich panels are investigated using ABAQUS/Explicit code. Firstly, a meso-structure model of the sandwich panels is constructed, which consists of the upper and lower skins, the honeycomb core and the skin/core welds. Defects are introduced by removing of skin/core welds, and the defect ratios are 1%, 2%, 4%, 8%, 16% and 32%. Next, the out-of-plane tensile, compressive and in-plane shear response and crushing of the sandwich panels under quasi-static loadings are calculated when different defect ratios are considered, respectively. Finally, the sensitivities of mechanical properties and failure behaviors of these defected sandwich panels are compared with that of an intact honeycomb sandwich panel. The numerical results indicate that defects introduced by randomly removing skin/core welds caused some mechanical properties a sharp decrease in the sandwich panels (e.g. a 1% defects caused more than 50% reduction in the out-of-plane tensile failure strain), while some properties exhibit a gradual decay, i.e. the compressive load plateau.