This article presents the first experimental, numerical, and analytical study of the elastoplastic shakedown response of an auxetic metamaterial structure that elucidates interactions between auxeticity and maximum shakedown loading capacity. The study aims to determine the safe elastoplastic shakedown limit of perforated auxetic aluminum sheet structures (AA5083-TO) with fixed void fraction (16.4%) under ambient cyclic asymmetric uniaxial loading conditions. The motivation is that shakedown-based designs can be used to expand the feasible design space under cyclic loading conditions compared to conventional yield-limited designs. Finite element analyses with calibrated hardening models are used to develop Bree load-interaction diagrams that are experimentally validated. It is found that shakedown occurs at stress levels up to almost four times the elastic limit of the structure for a fixed allowable equivalent strain level near three percent. This shakedown multiplier is also sensitive to the extent of auxeticity in the structure and a parametric study and analytical model are used to identify underlying mechanisms and a potential maximum condition.

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关于拉胀超材料的循环弹塑性安定行为：实验、数值和分析研究


本文首次对拉胀超材料结构的弹塑性安定响应进行了实验、数值和分析研究，阐明了拉胀性与最大安定载荷能力之间的相互作用。该研究旨在确定具有固定空隙率 (16.4%) 的穿孔拉胀铝板结构 (AA5083-TO) 在环境循环非对称单轴载荷条件下的安全弹塑性安定极限。其动机是，与传统的产量受限设计相比，基于安定的设计可用于扩展循环载荷条件下的可行设计空间。使用经过校准的硬化模型进行有限元分析来开发经过实验验证的 Bree 载荷相互作用图。研究发现，当固定允许等效应变水平接近百分之三时，安定发生在应力水平几乎达到结构弹性极限四倍的情况下。该安定乘数对结构的拉胀程度也很敏感，并且使用参数研究和分析模型来识别潜在的机制和潜在的最大条件。