Investigation of the effect of a viscous filler on the mechanical properties of metamaterials with negative and positive poisson's ratio when punching with a rigid impactor

Experiments were performed on the penetration of metamaterial samples based on ePLA plastic, prepared using a 3D printer, by a spherical rigid striker. Samples with a structure based on cells in the form of a concave hexagon had a negative Poisson's ratio (auxetics) and were compared with non-auxetics with a conventional honeycomb structure in the form of a convex hexagon in terms of their ability to resist penetration. Structures with chirality were also considered. Experiments were conducted under conditions of air filling of the structure cells and filling with gelatin. The fact of a significant increase in resistance to penetration was established when auxetic chiral samples were filled with gelatin compared to those filled with chiral non-auxetics. For chiral metamaterials with gelatin, a deviation in the direction of the striker's movement after leaving the sample being penetrated was recorded.