The effect of impact velocity to the reaction force, the deformation length and the deformation mode on a thin aluminum tube

Abstract

Many people have conducted research related to the thin tubes as energy absorbers. The response of the specimens when receiving axial loads at low-velocity impact and high-velocity impact has been carried out by many researchers. In this study, the effect of impact velocity on the response of specimen reaction forces and the factors that influence on thin aluminum tube specimens with fixed impact energy will be examined.The specimen used in this research is a thin aluminum tube with an outer diameter of 32 mm and a thickness of 1 mm with a length of 120 mm. The axial force is the impact of the impactor steel with varying mass adjusted to varying velocities with a fixed impact energy of 785 Joules. The response of reaction force from specimens, maximum deformation in each specimen and deformation mode was observed at each increase of impact velocity. Modeling of the experiment is prepared by the Finite Element Method using the ANSYS 19 Academic Version.The results of the study confirm that the higher the impact velocity on fixed energy, the greater the maximum reaction force. On the other hand, the smaller the maximum deformation. In general, there is a change in deformation mode, which is non-axisymmetric at low speeds and axisymmetric at higher speeds. The axisymmetric deformation mode affects the maximum deformation to be smaller, and the maximum reaction force becomes more significant at fixed energy. In this study, it was found that at an increased impact velocity of 140 m / s to 150 m / s there was a change in deformation mode from non-axisymmetric to axisymmetric.