A comprehensive research on SNPR structures with energy absorption and bearing capacities: topology optimization, numerical simulation and experimental verification

The physical applications of negative Poisson's ratio structures of insufficient bearing capacity were limited. The topologies of high stiffness negative Poisson's ratio (T-SNPR) were designed, and the bearing and energy absorption performance of their three-dimensional structures (S-SNPR) were analyzed using the finite element method. Furthermore, the experimental results of the second SNPR structure (S-SNPR-2) specimen produced by wire electro discharge machining (WEDM) were identical to the numerical results, and the error values of force and energy absorption were 8.9% and 14.9%, respectively. The SNPR-2 obtained the higher EA value of 83 kJ, SEA value of 2.3 kJ kg-1, and bearing force value of 1050 kN, as well as the more extensive compress stroke strain value of 0.18 than S-SNPR-1. Under compression and high-velocity impact, the S-SNPR-2 structure with a relative density value of 0.57 obtained better bearing, energy absorption, and impact resistance capacities. Under low- and medium-velocity impact, the S-SNPR-2 structure with a relative density value of 0.52 obtained better bearing and impact resistance characteristics, and the S-SNPR-2 structure with a relative density value of 0.57 had better energy absorption performance. The S-SNPR-2 proposed in this paper has a good application prospect as an energy-absorbing component in coal mining supporting equipment.