This study focused on the damage of permanent magnets(NdFeB) in the electromagnetic buffer under the intensive impact load. According to the constitutive characteristics of the permanent magnets, a constitutive model suitable for NdFeB called damage-modified ZWT was determined. Furthermore, the specific parameters in the constitutive model were determined by fitting the constitutive curve. Then the incremental expression was established for the constitutive model and the model was embedded into ABAQUS via the VUMAT subroutine interface. A dynamic model of the electromagnetic buffer was established and calculated. After that the evolution and distribution law of damage in permanent magnets under the intensive impact load were clarified by analyzing the finite element results. Finally the damage of the device is reduced by optimizing the geometric parameters. The results show that the permanent magnets near the inner ring are damaged more from the radial distribution of the damage and the permanent magnets on both sides are damaged more from the lateral distribution of the damage, which provides a reference for the design of electromagnetic buffers.

中文翻译：

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强烈冲击载荷下电磁缓冲器中永磁体的损坏

这项研究的重点是在强烈冲击载荷下电磁缓冲器中永磁体（NdFeB）的损坏。根据永磁体的本构特征，确定了适用于NdFeB的本构模型，称为损伤修正ZWT。此外，通过拟合本构曲线来确定本构模型中的特定参数。然后为本构模型建立增量表达式，然后通过VUMAT子例程接口将模型嵌入ABAQUS。建立并计算了电磁缓冲器的动力学模型。通过分析有限元结果，阐明了强冲击载荷下永磁体损伤的演化规律和分布规律。最后，通过优化几何参数可以减少设备的损坏。结果表明，内圈附近的永磁体受损伤的径向分布的影响更大，两侧的永磁体受损伤的侧向分布的损伤更大，这为电磁缓冲器的设计提供了参考。