High-rate impact resistance and broadband shock mitigation in reusable 3D-printed sutural composites via bidirectional interfacial shear

Developing protective structures that withstand high-strain-rate impacts while remaining reusable poses a significant challenge in impact engineering. This study presents a bio-inspired 3D sutural composite designed to mitigate high-velocity shocks via a topology-driven bidirectional interfacial shear mechanism. Using Split-Hopkinson Pressure Bar (SHPB) experiments and explicit finite element simulations, we characterize the dynamic response of the composites at strain rates of 500–2500 s⁻¹. The results demonstrate that the 3D sutural architecture exhibits significantly greater impact resistance than its 2D counterpart, achieving an energy absorption efficiency of ∼0.90 and broadband stress-wave attenuation exceeding 85%. Analysis reveals that the 3D interlocking topology induces geometric dispersion and multiaxial shear deformation in the compliant phase, overcoming the in-plane limitations of 2D designs and effectively acting as a broadband shock filter. Crucially, unlike sacrificial absorbers, the composites exhibit stable cyclic durability, maintaining structural integrity and ∼90% energy absorption efficiency over eight consecutive impacts at 1000 s⁻¹. These findings establish a quantitative design framework for lightweight, non-destructive protective systems capable of adaptive wave management in aerospace and advanced structural applications.