Investigation on metal composite corrugated energy absorbers

The crushing behavior of corrugated metal and metal-composite tubes under quasi-static axial compression is experimentally investigated. Several experiments were carried out to compare the failure mechanism of metal-composite tubes with that of metallic tubes. The experimental results revealed that the corrugated metal-composite specimens exhibit excellent energy dissipation properties, including a reduced initial peak response and consistent load-displacement diagram. This indicates that the crushing behavior and energy absorption capacity of corrugated metallic tubes can be significantly enhanced by applying a composite filament-wound layer. In this dissertation, a new developed axially corrugated thin-walled tube has been introduced for improving energy absorption characteristics. The forming process of the corrugations on the tubes has been also described. A comprehensive experimental and numerical analysis have been conducted in order to investigate the effects of various geometrical parameters on crushing behavior of the structure. It can be seen that by the use of such corrugation, there is much more efficient crushing via a more uniform force-displacement diagram while there is also considerable improvement in other crashworthiness characteristics. Subsequently, the experimental data is verified by a finite element simulation on all investigated tubes. An efficient model in axial loading has been obtained which is offering a perfect concertina form. The obtained model deforms through an inversion mode causing an extra frictional force between the inverted part of the tube resulting in a considerable increase in SEA, mean force, and consequently CFE. Finally, the selected model has been investigated under oblique loading in different crushing angle where it exhibits improved performance. Moreover, The theoretical solution based on experiment and modified simplified super folding element (MSSFE) theory is proposed that depends on the number of plastic hinge line, wall thickness, length of structure and flow stress of material. The comparison between theoretical solution and experiment shows a good agreement with acceptable errors.