Dynamic Responses of Nare-Like Voronoi Structure under Impact Loading

As an effective structure system for resisting the compression, the nacre composite structure has random Voronoi structure at a microscopic level and good mechanical performance. In this study, a three-dimensional Voronoi model consisting of aluminum/vinyl composite structure was presented to investigate the dynamic responses of nare-like Voronoi model under impact loading. Firstly the stochastic Voronoi model was built using the Voronoi technology, and then the adhesive layers were introduced between random polygonal aluminium sheets to simulate the bonding and delaminating processes. Via the maximum deformation, damage distribution and dissipation energy, the mechanical performances of Voronoi plate model were evaluated and compared with those of the regular plate model. The results showed that the Voronoi model is in favor of energy spreading and absorbing, reducing the stress concentration and making the energy sharing mechanism work better. But the impact damage of the regular plate model is concentrated near the impacting point of the bullet. Finally the influences of adhesive thickness and block size on mechanical performances were discussed. It was indicated that the block size has little effect on the impact resistance of the Voronoi model while the adhesive thickness exerts significant influence on the damage dissipation energy and plastic energy. It was found that the thinner is the adhesive thickness, the better is the impact resistance performance of the model.