Dynamic Mechanical Behavior of Sinusoidal Corrugated Dual-Phase Lattice Metamaterials by Additive Manufacturing

Background: Additive manufacturing enables lattice metamaterials designed with complex architectures. However, how to design the architecture for greater impact resistance remains not fully explored. Objective: This study aims to develop bio-inspired dual-phase metamaterials and examine their dynamic performance. Methods: By mimicking the impact region of mantis shrimp, dual-phase lattices (DPLs) were designed by incorporating reinforcement phase (RP) as sinusoidal corrugated forms with multiple phase differences. Then, those metamaterial composites were fabricated using additive manufacturing techniques with stainless steel powder and compressed under different strain rates. Results: Under quasi-static compression conditions, DPLs demonstrated superior energy absorption capacity compared to traditional homogeneous lattice materials. For DPLs with various phase architectures, the differences in load-bearing capacity, failure modes, and impact energy dissipation time became more pronounced as strain rate increased. The dual-phase lattice metamaterials showed 2.83 times greater strength values under low-speed impact conditions than those under quasi-static compression, demonstrating excellent strain-rate hardening effects. Failure modes were found to be associated with both RP arrangement patterns and compressive strain rates. However, the shear band propagation paths under low-speed impact were consistent with those observed under quasi-static compression, indicating that RP pattern governed the shear band distribution irrespective of impact velocity. Conclusions: This work provided valuable insights for the architecture design of lattice metamaterials in dynamic application.