Origami-Inspired hierarchical sandwich structures for enhanced multiscale mechanical performance

• Curved-crease hierarchical origami cores redirect loads from local buckling to stable global deformation. • Geometry-driven stress redistribution governs stiffness and damage evolution across scales. • Hexavoid architecture achieves 40% higher energy absorption than honeycomb cores. • Origami topology couples’ compression, bending, and impact resistance within one structure. This study introduces a new class of additively manufactured origami-inspired hierarchical sandwich structures that exploit curved-crease geometry to achieve multiscale mechanical enhancement across diverse loading conditions. Three previously unreported core architectures, Hexavoid (HV), Rhomboid (RV), and Octavoid (OV), are developed and embedded into full sandwich panels, enabling a systematic investigation of how geometry-driven deformation governs stiffness, strength, and energy dissipation. Unlike conventional honeycomb cores that rely on localized wall buckling, the proposed architecture activates controlled in-plane contraction and distributed folding, producing stable load transfer between face sheets and delayed damage localization. Experiments reveal that the HV core delivers the most balanced performance, achieving a 40% increase in specific energy absorption and a 76% rise in elastic modulus under quasi-static compression relative to honeycomb benchmarks. Under flexural loading, the same architecture exhibits over threefold improvement in stiffness and fourfold enhancement in absorbed energy. Low-velocity impact and indentation tests further demonstrate that auxetic confinement and curved-crease deformation suppress premature failure, enabling up to 38% higher energy dissipation. Finite element analysis confirms that these gains arise from topology-induced stress redistribution and stretching-assisted deformation. The results identify curved-crease origami as a robust design strategy for lightweight sandwich structures combining impact resistance and energy absorption.