DEFORMATION OF METALLIC THIN-WALLED HOLLOW SPHERES UNDER DYNAMIC COMPRESSION

Dynamic compressive behavior of single metallic hollow spheres is fundamental to hollow sphere structures. Based on numerical simulations performed in this study, normalized stress-strain curves of a single metallic hollow sphere were obtained and compared with experimental results. According to the curves and deformation modes, the deformation process was summarized into six stages. The effects of the diameter-to-wall thickness ratio and the impact velocity on the dynamic deformation process were further investigated. It was found that, with an increase in the diameter-to-wall thickness ratio, the failure modes of side walls transformed from bending to buckling and the reverse turnover of internal surfaces transformed from bottom to top. Moreover, as the impact velocity increases, the bottom shell of the hollow sphere dimpled sooner and the deformation asymmetry was much larger.