Investigation of the local enhancement of cellular materials based on 2D Voronoi model

Abstract

Stress enhancement has been observed when cellular materials were subjected to intense impact loading, leading to severe damage to the objects protected. This may be caused by densification and non-uniform deformation of materials. Current investigations mainly centres on the shock wave generated in the densification. However, the local non-uniform deformation may lead to the possible local enhancement in the plateau crushing stage, so this phenomenon is qualitatively studied by employing the 2D Voronoi models. The effect of the cell shape irregularity was taken into consideration, and the possible interpretations of local enhancement are discussed. Meanwhile, a method based on optimal local deformation gradient is adopted to calculate the local strain field. This research provides valuable insight into the reliability of the cellular materials as a protective structure.

Keywords:

• Cellular materials
• Pulse loading
• Stress enhancement
• Local strain field
• Wave impedance