The effects of adding an extra layer within a sandwich panel and two different core types in top and bottom cores on low velocity impact loadings are studied experimentally in this paper. The panel includes polymer composite laminated sheets for faces and the internal laminated sheet called extra layer sheet, and two types of crushable foams are selected as the core material. Low velocity impac...

We manufactured sandwich-walled cylindrical shells with aluminum pyramidal truss core of constant curvature employing an interlocking fabrication technique for the metallic core. The skins were made of carbon-fiber reinforced composites and co-cured with the metallic truss core. Thereafter, we carried out axial compression tests on some representative samples to investigate the failure modes of...

This is the first study on the free vibrational behavior of sandwich panels with flexible core in the presence of smart sheets of oil which is capable of the excitation of magnetic field. In order to model the core, the improved high order theory of sandwich sheets was used by a polynomial with unknown coefficients first degree shear theory was used for the sheets. The derived equations based o...

Novel tetrachiral honeycomb structures are evaluated for the first time from the vibroacoustic point of view. A numerical method based on Bloch wave approximations for Finite Element models of the unit cells is applied to simulate the pass-stop band characteristics of these cellular solids. Experimental modal analysis and modal densities are measured on honeycomb panels and sandwich plate, and ...

This paper presents an investigation on energy absorption characteristics of nano-reinforced panels, laminated face sheets and sandwich composites in high velocity ballistic and low velocity punch-shear experiments. The vinyl ester panels were reinforced with 1.25 and 2.5 wt. percent nanoclay and exfoliated graphite platelets. Three different face sheets were manufactured with E-glass, Owens Co...

A comparative study of different modeling approaches for predicting sandwich panel buckling response is described. The study considers sandwich panels with anisotropic face sheets and a very thick core. Results from conventional analytical solutions for sandwich panel overall buckling and face-sheet-wrinkling type modes are compared with solutions obtained using different finite element modelin...