Dynamic buckling behaviour of aluminum alloy thin cylindrical shell under axial impact load: Experimental study

In this study, we investigate the intricate dynamic buckling behaviour of aluminium alloy thin-walled cylindrical shells subjected to instantaneous axial loads. Our investigation aimed to provide a comprehensive understanding of the structural response and failure mechanisms under such extreme conditions. First, a large-diameter Hopkinson pressure bar was employed to impose impacts on aluminium alloy thin-walled cylindrical shells featuring varying diameter-to-thickness ratios at distinct velocities. Subsequently, we leveraged stress wave inversion techniques and the digital image correlation method to precisely extract the deformation and stress information of cylindrical shells during their dynamic buckling process. Second, the influences of the geometric dimensions and impact velocities on the dynamic buckling load borne by the cylindrical shell were explored. Finally, the effect of the impact velocity on the buckling modes exhibited by thin-walled cylindrical shells was thoroughly investigated using finite element simulations. The results indicated that the dynamic buckling load of the cylindrical shell exhibited an inverse correlation with its diameter-to-thickness ratio, and was directly proportional to the impact velocity. As the impact velocity increased, the buckling mode of the thin shell transformed from a diamond-like pattern to a distinct ring mode. The results of this study offer valuable experimental insights that can serve as a reference for future investigations on the dynamic impact buckling behaviour and energy absorption mechanisms of cylindrical shells.