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arXiv · 2310.04748

Leveraging yield buckling to achieve ideal shock absorbers

Wenfeng Liu·Shahram Janbaz·David Dykstra·Bernard Ennis·Corentin Coulais
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Abstract

The ideal shock absorber combines high stiffness with high energy absorption whilst retaining structural integrity after impact and is scalable for industrial production. So far no structure meets all of these criteria. Here, we introduce a special occurrence of plastic buckling as a design concept for mechanical metamaterials that combine all the elements required of an ideal shock absorber. By striking a balance between plastic deformation and buckling, which we term yield buckling, these metamaterials exhibit sequential, maximally dissipative collapse combined with high strength and the preservation of structural integrity. Unlike existing structures, this design paradigm is applicable to all elastoplastic materials at any length scale and hence will lead to a new generation of shock absorbers with enhanced safety and sustainabilty in a myriad of high-tech applications.

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Wenfeng Liu, Shahram Janbaz, David Dykstra, Bernard Ennis, Corentin Coulais. 2023-10-07. Leveraging yield buckling to achieve ideal shock absorbers. https://arxiv.org/abs/2310.04748

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