On the quasi-static and impact responses of aluminum honeycomb under combined shear-compression

Abstract A new Rotatable Hopkinson bar is proposed for investigating the impact shear-compressive behavior of cellular materials with separated normal and shear responses. Validating works by numerical simulations on the whole loading process indicates that this dynamic shear-compression method provides a quite accurate measurement on the specimen forces and deformation in both shear and normal directions. With this new design, the impact shear-compression responses of a 5052 honeycomb in TW plane are investigated at different loading angles and compared with the corresponding quasi-static results. Good reproducibility is achieved for most of the loading cases in terms of normal stress/normal displacement and shear stress/shear displacement curves, except the ones in which different deformation modes co-exist. The experiment results from both quasi-static and dynamic loadings reveal that the normal strength of the honeycomb will be weakened, but the shear strength becomes more important with an increasing shear deformation component. A crush envelope in elliptical shape is found to describe the average shear and compressive strengths of honeycomb for both quasi-static and dynamic loadings. The deformation modes of honeycombs under combined shear-compression are examined for all the testing results and some influencing factors, such as specimen dimensions, contact conditions and specimen geometric imperfections are confirmed.