Mechanical performance and energy absorption of hybrid TPMS structures under quasi-static crushing

• Hybrid TPMS rod-sheet structures transcends the stiffness vs. energy absorption trade-off in lattices. • Failure shifts from brittle shear to stable layer-collapse, proven by DIC and FEA. • A hybrid structures with sheet-based Primitive and rod-based Primitive demonstrates the best combined mechanical performance and energy absorption capability. Additive manufacturing (AM) enables the fabrication of triply periodic minimal surface (TPMS) lattice architectures with tailored mechanical properties; however, single-topology designs are inherently constrained by the trade-off between strength and energy absorption. To overcome this limitation, this study systematically investigates the mechanical behavior and energy absorption characteristics of both single-topology lattices and complementary hybrid architectures fabricated via laser powder bed fusion (LPBF) using AlSi7Mg alloy powder. Digital image correlation (DIC) and finite element analysis (FEA) reveal a fundamental shift in failure behavior: the characteristic brittle 45° shear fracture observed in monolithic AlSi7Mg matrices is effectively replaced by a stable, layer-by-layer collapse in hybrid architectures. This transition is attributed to performance complementarity, which integrates the high strength of rod-based components with the stable energy dissipation capabilities of sheet-based networks. Consequently, the PSPR hybrid architecture exhibits simultaneous enhancements in load-bearing capacity and energy absorption efficiency, with the measured energy absorption reaching 11.56 ± 0.25 MJ/m 3 —representing a 71.77% improvement compared to single-topology designs. These findings indicate that hybrid TPMS architectures effectively overcome the intrinsic limitations of conventional single-topology designs, providing a promising pathway for the development of high-performance, damage-tolerant components suitable for critical engineering applications