Mechanical Performance and Deformation Mechanisms of Hybrid Cylindrical TPMS Lattices with Gradient Wall Thickness

Lattice metamaterials possess lightweight, high strength, and excellent energy absorption, making them promising for engineering applications. Their mechanical properties can be tuned by cell topology and structural design. This study proposes a multi-degree-of-freedom hybrid strategy for cylindrical TPMS lattices. Three uniform types (Primitive, Gyroid, IWP) were fabricated and validated through experiments and simulations. Radial, axial, and circumferential hybridizations were then explored, revealing distinct deformation and energy absorption mechanisms: CMA structures showed multi-stage behavior, while CMR and CMC offered longer plateau stages and higher stresses. Inspired by biological architectures, gradient wall thickness designs were introduced, significantly improving performance. Notably, CMR-GPI213 and CMC-PIG312 increased specific energy absorption by 24% and 14.8%, and CMA-GIP312 reduced peak force by 37.7% without sacrificing absorption. These results demonstrate that hybridization and gradient design enable precise regulation of force response and deformation, offering a novel paradigm for optimizing cylindrical TPMS lattices.