An investigation on the energy absorption capability of aluminum foam-filled multi-cell tubes

Abstract

Aluminum foams are employed more and more in the automobile sector in order to increase the crashworthiness of energy absorbers. This study examines the energy absorption potential of multi-cellular tubes filled with Al foams. The mean crush forces of foam-filled tubes are calculated using a theoretical model that takes into account the effects of the tube, the foam, and their interaction. A numerical model including the damage constitutive equations is also built to examine the additional crashworthiness properties, such as specific energy absorption and crush force efficiency. The numerical and theoretical models are validated through experiments under quasi-static axial loading, where crashworthiness metrics and deformation images of the tubes are compared. It is observed that the inclusion of damage criteria in the numerical simulation can accurately simulate the deformation of the tubular specimens. It was discovered that foam-filled tubes efficiently absorbed more energy without considerably adding to their total weight compared to hollow, thin-walled tubes. Inserting aluminum foam inside the T4 multi-cell tube improved energy absorption (EA) and crush force efficiency (CFE) by 140 and 84%, respectively. Similarly, inserting aluminum foam inside the T8 multi-cell tube improved EA and CFE by 60 and 34%, respectively. It is also found that the mean force values of empty and foam-filled multi-cell tubes can be predicted using an empirical formula with an error less than 5 and 15%, respectively. Due to their high stiffness-to-weight ratio and energy absorption capacity, foam-filled multi-cell tubes can be utilized as energy absorbers to reduce damage and additional harm to the passengers in the event of an accident.