A new cohesive phase-field (CPF) interface fracture model is proposed in this paper. It employs an exponential function for the interpolation of fracture energy between the bulk phase and the interface, and its effective interface fracture energy is solved based on the Euler–Lagrange equation of the phase-field theory and the consistency to the cohesive zone model (CZM) in the sharp interface concept. Comparison to other interface models in the literature clearly shows that the above energy consistency is essential to ensure the insensitivity of the results to the length-scale parameters for regularization of the crack surface and of the interface. The proposed interface model can be conveniently implemented via the relaxation solution of an Allen–Cahn equation, which offers high flexibility in handling structures of complicated interface topology. The proposed CPF interface model is employed further to derive a thermodynamically consistent chemo-mechanical model relevant to Lithium-ion battery materials. Finite-element simulations confirm the model’s ability to recapture the competition between bulk and interface fractures, while also demonstrate its merits of length-scale insensitivity and consistency with CZM results. The model is eventually applied in polycrystalline electrode particles, which are reconstructed from images with segmented interfaces, confirming the expected computational advantages and the length-scale insensitivity in multi-physical context.

中文翻译：

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一种长度尺度不敏感的内聚相场界面模型：在锂离子电池材料中并行体和界面断裂模拟中的应用


该文提出了一种新的内聚相场 （CPF） 界面断裂模型。它采用指数函数对体相和界面之间的断裂能量进行插值，其有效界面断裂能基于相场理论的欧拉-拉格朗日方程和与夏普界面概念中内聚区模型 （CZM） 的一致性来求解。与文献中其他界面模型的比较清楚地表明，上述能量一致性对于确保结果对裂纹表面和界面正则化的长度尺度参数不敏感至关重要。所提出的界面模型可以通过 Allen-Cahn 方程的松弛解方便地实现，该方程在处理复杂界面拓扑结构方面提供了高度的灵活性。所提出的 CPF 接口模型进一步用于推导出与锂离子电池材料相关的热力学一致的化学机械模型。有限元仿真证实了该模型重新捕获体裂缝和界面裂缝之间竞争的能力，同时也证明了其长度尺度不敏感和与 CZM 结果一致的优点。该模型最终应用于多晶电极粒子，这些粒子是从具有分段界面的图像中重建的，证实了预期的计算优势和多物理环境中的长度尺度不敏感。