Bioinspired fabric architecture harnessing anisotropy for omnidirectional mechanical protection.

Abstract

Powder bed fusion (PBF)-printed fiber-reinforced composites often exhibit powder-recoating-induced anisotropy, resulting in direction-dependent mechanical behavior that limits reliability under multidirectional loading. Inspired by the surface-following alignment of enamel rods in tooth enamel, we develop a fabric architecture that integrates build-orientation-controlled fiber alignment with a staggered interlocking topology of cubic unit cells. By optimizing build orientation and leveraging its shape-adaptive structural feature, this bioinspired architecture enables surface-following reinforcement, thereby harnessing anisotropy and achieving spatially uniform mechanical enhancement. Vacuum-confinement-induced jamming further enhances strength and energy absorption, while shifting the postyield response from bending-dominated deformation to friction-governed tilting of the interlocked unit cells, improving recovery ratio and overcoming the conventional trade-off between strength and recoverability. Consequently, this architecture demonstrates 1.85× higher specific strength and 1.92× higher specific energy absorption than the nonoptimized reference without vacuum confinement, ranking it among the leading lightweight load-bearing and energy-absorbing architectures. Additionally, the proposed fabric architecture delivers spatially uniform mechanical protection, a capability that remains challenging to achieve using conventional PBF-printed fiber-reinforced architectures. This work introduces a synergistic strengthening strategy that integrates structural design, process control, and external confinement. Importantly, we propose a general architecture-driven design paradigm that transforms mechanical anisotropy from a limitation into a performance advantage. The resulting fabric architecture delivers high-performance omnidirectional mechanical protection across diverse applications, such as protective casings of sensitive underwater systems and shape-adaptive protective covers.