Impact Mechanics of Topologically Interlocked Material Assemblies

The objective of the present study is to provide understanding of potential energy absorption and dissipation mechanisms and benefits of topologically interlocked material (TIM) assemblies under impact loading. The study is motivated by earlier findings that TIMs under low rate loading demonstrated attractive properties including the capability to arrest and localize cracks and to exhibit a quasi-ductile response even when the unit elements are made of brittle materials. It is hypothesized that TIMs due to their modularity would possess advantageous impact characteristics. In order to test this hypothesis, a series of computational experiments on the dynamic loading of TIMs are conducted. Results obtained in this study are presented for a planar TIM configuration based on a dense packing of tetrahedral unit elements to form an energy absorption layer. Finite element models are calibrated on samples fabricated using fused deposition modeling (FDM) additive manufacturing (AM). With employing the Lambert–Jonas formula to interpret the numerical data, it is demonstrated that TIMs can absorb more impact energy than conventional solid plates. An extended Lambert–Jonas model is defined such that accurate description of the impact response of TIMs is obtained.