Recent studies on magnetically hard, particle-filled magnetorheological elastomers (-MREs) have revealed their stretch-independent magnetization response after full pre-magnetization. We discuss this phenomenon, focusing on incompressible, isotropic, particle-filled -MREs. We demonstrate that the fully dissipative model of Mukherjee et al. (2021) for arbitrary loads can be reduced, under physically consistent assumptions, to the energetic model of Yan et al. (2023), but not that of Zhao et al. (2019). The latter two are valid for small magnetic fields around an already pre-magnetized state. When the pre-magnetized MRE undergoes non-negligible stretching, the Zhao et al. (2019) model yields predictions that disagree with experiments due to its inherent stretch-dependent magnetization response. In contrast, the Mukherjee et al. (2021) and Yan et al. (2023) models are able to accurately capture this important feature present in pre-stretched -MREs. However, for inextensible slender structures under bending deformation, where stretching is negligible, the Zhao et al. (2019) model provides satisfactory predictions despite its underlying assumptions. Our analysis reveals that, in the fully dissipative model, magnetization can be related to an internal variable but cannot be formally used as one, except for ideal magnets, and is subject to constitutive assumptions. Furthermore, the magnetization vector alone is insufficient to describe the magnetic response of an MRE solid; the introduction of one of the original Maxwell fields is necessary for a complete representation.

中文翻译：

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不可压缩各向同性硬磁流变弹性体中与拉伸无关的磁化


最近对硬磁颗粒填充磁流变弹性体 (-MRE) 的研究揭示了它们在完全预磁化后的与拉伸无关的磁化响应。我们讨论了这种现象，重点关注不可压缩、各向同性、颗粒填充的 MRE。我们证明了 Mukherjee 等人的完全耗散模型。在物理一致的假设下，任意载荷的 (2021) 可以简化为 Yan 等人的能量模型。 （2023），但不是赵等人的。 （2019）。后两者对于已预磁化状态周围的小磁场有效。当预磁化的 MRE 经历不可忽略的拉伸时，Zhao 等人。 （2019）模型由于其固有的拉伸相关磁化响应而产生与实验不一致的预测。相比之下，Mukherjee 等人。 （2021）和Yan等人。 (2023) 模型能够准确捕捉预拉伸-MRE 中存在的这一重要特征。然而，对于弯曲变形下不可延伸的细长结构，拉伸可以忽略不计，Zhao 等人。 （2019）模型尽管有基本假设，但仍提供了令人满意的预测。我们的分析表明，在完全耗散模型中，磁化强度可以与内部变量相关，但不能正式用作内部变量（理想磁体除外），并且受本构假设的影响。此外，单独的磁化矢量不足以描述 MRE 固体的磁响应；为了完整的表示，引入原始麦克斯韦场之一是必要的。