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arXiv · 2502.17083

Mechanical non-reciprocity programmed by shear jamming in soft composite solids

Chang Xu·Shuaihu Wang·Hong Wang·Xu Liu·Zemin Liu·Yiqiu Zhao·Wenqi Hu·Qin Xu
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Abstract

Mechanical non-reciprocity-manifested as asymmetric responses to opposing mechanical stimuli-has traditionally been achieved through intricate structural nonlinearities in metamaterials. However, continuum solids with inherent non-reciprocal mechanics remain underexplored, despite their promising potential for applications such as wave guiding, robotics, and adaptive materials. Here, we introduce a design principle by employing the shear jamming transition from granular physics to engineer non-reciprocal mechanics in soft composite solids. Through the control of the interplay between inclusion contact networks and matrix elasticity, we achieve tunable, direction-dependent asymmetry in both shear and normal mechanical responses. In addition to static regimes, we demonstrate programmable non-reciprocal dynamics by combining responsive magnetic profiles with the anisotropic characteristics of shear-jammed systems. This strategy enables asymmetric spatiotemporal control over motion transmission, a previously challenging feat in soft materials. Our work establishes a novel paradigm for designing non-reciprocal matter, bridging granular physics with soft material engineering to realize functionalities essential for mechano-intelligent systems.

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Chang Xu, Shuaihu Wang, Hong Wang, Xu Liu, Zemin Liu, Yiqiu Zhao, Wenqi Hu, Qin Xu. 2025-02-24. Mechanical non-reciprocity programmed by shear jamming in soft composite solids. https://doi.org/10.1038/s41563-025-02407-3

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