In this paper, the influence of foam filling of aluminum honeycomb core on its in-plane crushing properties is investigated. An aluminum honeycomb core and a polyurethane foam with densities of 65, 90, and 145 kg/m³ were used to produce foam filled honeycomb panels, and then experimental quasi-static compression tests were performed. Moreover, finite element model, based on the conducted tests, was developed. In the finite element analyses, three different polyurethane foams were used to fill three different honeycomb cores. The effects of foam filling of aluminum honeycomb core on its in-plane mechanical properties (such as mean crushing strength, absorbed energy, and specific absorbed energy) were analyzed experimentally and numerically. The results showed that the foam filling of honeycomb core can increase the in plane crushing strength up to 208 times, and its specific absorbed energy up to 20 times. However, it was found that the effect of foam filling decreases in heavier honeycombs, producing an increment of the above mentioned properties only up to 36 and 6 times, respectively.

The aim of this research is the investigation of foam-filled honeycomb sandwich panels under in-plane impact loading and the analysis of their crashworthiness. This paper presents a finite element analysis of foam-filled honeycomb sandwiches under in-plane impact loading. Three different aluminium honeycombs filled with three different polyurethane foams were considered in the numerical simulation, and results were compared with those obtained for bare honeycomb panels. For what concerns the crashworthiness analysis, the response of the foam-filled honeycomb panels under out-of-plane impacts was compared with those of unfilled honeycomb panels and circular tubes.

The honeycomb sandwiches are widely used in the transportation engineering for the realization of lightweight and crashworthy structures. However their application requires a better understanding of their impact response. Aims of this paper are the numerical investigation of aluminium honeycomb sandwiches subjected to low-velocity impact tests and the validation of finite element (FE) results. Before and after the low-velocity impact tests at different velocities, three dimensional (3D) reconstructions of the honeycomb panels have been carried out by a computed tomographic system in order to acquire exactly the dimension and the shape of the damage and to obtain information about geometry and cells defects. The FE models have been computed from CT data of the undamaged panels. The direct comparison has been done by superimposing the deformed images obtained from FE analyses and from 3D CT space reconstructions. The numerical model was also validated comparing the FE results with experimental data.

As a common type of energy absorbers, thin-walled structures have been extensively used in crashworthiness application in many industries. The goal of this research is the optimisation of the crushing parameters of corrugated tubes in terms of the number and shape of corrugations. Six different configurations were experimentally investigated; one refers to the straight tube without configurations and the others to corrugated tubes with different geometrical parameters. First, lateral compression tests were carried out and the experimental results were used to validate the finite element models. Other six different configurations of corrugated tubes were analysed by means of finite element simulations. The obtained results demonstrate the advantage of the corrugated tubes with respect to the straight tube in terms of the total absorbed energy and the crushing load. Moreover, the geometrical shape of corrugation (i.e. the ratio of corrugation base to its depth) plays an important role in enhancing the efficiency of the corrugated tubes.