Abstract
Architected lattice metamaterials offer tunable, exceptional mechanical performance through precisely engineered microarchitectures, yet an intrinsic trade-off between strength and toughness remains a fundamental design challenge. Here, a class of aperiodic architected metamaterials guided by the golden ratio - a geometric principle emblematic of natural balance and structural harmony-is introduced to overcome this limitation. The concept is validated via additive manufacturing of conventional periodic, hierarchical periodic, and golden-ratio-guided aperiodic lattices, along with their interpenetrating phase composite (IPC) counterparts. The aperiodic architectures exhibit significantly enhanced damage tolerance under monotonic loading, with increases of 84.24% and 42.45% in ultimate load, and 277.43% and 128.13% in initial fracture energy, for the lattice and IPC metamaterials, respectively. Under cyclic loading, only the aperiodic IPC withstands five tensile cycles at 350 N before incurring damage, whereas all other architectures fail during the initial cycle. These improvements stem from the unification of local geometric heterogeneity and global order in the golden-ratio-guided aperiodic architecture, which alleviates stress concentrations and promotes spatial delocalization of damage-tolerence regions. As a result, crack paths become more tortuous and adaptive, enhancing energy dissipation and resistance to fracture. These findings establish golden-ratio-guided aperiodicity as a robust design paradigm for next-generation damage-tolerant metamaterials.