Experimental and finite element analysis of the effect of geometrical parameters on the mechanical behavior of auxetic cellular structure under static load

The auxetic structures are structures with negative Poisson ratio that behave under tension or compression as opposed to ordinary materials. Due to the unique mechanical properties, such as increasing the resistance against collision and different formation capability, extensive research is ongoing. In this research, using finite element modeling, simulation of various geometrical parameters of auxetic cell structures have been studied. Verification of the results is done by experimental tests of the model made by 3D printing technology. By introducing different measurement methods such as image processing, the modeling results are compared with experimental tests that show high accuracy results. In this analysis, the effect of the angle between the cell components, unit cell dimensions, thickness, and density of cells are investigated. In addition, new designs to improve the performance of the auxetic structure such as the use of different thicknesses are studied. Auxetic structures are part of advanced structures such as composites and biomaterials with diverse properties and applications in various fields such as military, medical, textile, and aerospace industries. Auxetic applications are excellent in absorbing impact force as bulletproof vests and similar equipment, high strength to weight in lightweight sandwich panels, and in tissue engineering like stent application.