Polymer–crystal composite particles formed by crystals coated with binders are widely used in the fields of medicine, energy, the chemical industry, and civil engineering. Binder content is an important factor in determining the mechanical behavior of composite particles. Therefore, this study aimed to investigate the underlying effect of binder coatings in the fracture micromechanics of polymer–crystal composite particles using the discrete element method (DEM). To achieve this objective, realistic particle and crystal shapes were first obtained and reconstructed based on X-ray micro-computed tomography (μCT) scanning and scanning electron microscope (SEM) images. A series of single particle crushing tests and DEM simulations were conducted on real and reconstructed polymer–crystal composite particles, respectively. Based on the experimental and DEM results, the effect of binder coatings on the crushing strength and crushing patterns of polymer–crystal composite particles was measured. Moreover, the micromechanics of the development and distribution of microcracks was further investigated to reveal the mechanism by which binder coatings affect polymer–crystal composite particles.

中文翻译：

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使用离散元方法，粘合剂涂层对聚合物-晶体复合颗粒断裂行为的影响

由晶体包覆粘合剂形成的聚合物-晶体复合颗粒广泛应用于医药、能源、化工和土木工程领域。粘合剂含量是决定复合颗粒机械性能的重要因素。因此，本研究旨在使用离散元法 (DEM) 研究粘合剂涂层对聚合物-晶体复合颗粒断裂微观力学的潜在影响。为了实现这一目标，首先基于 X 射线显微计算机断层扫描 (μCT) 扫描和扫描电子显微镜 (SEM) 图像获得和重建逼真的颗粒和晶体形状。分别对真实和重建的聚合物-晶体复合颗粒进行了一系列单颗粒破碎试验和 DEM 模拟。基于实验和 DEM 结果，测量了粘合剂涂层对聚合物-晶体复合颗粒的抗碎强度和抗碎模式的影响。此外，进一步研究了微裂纹发展和分布的微观力学，以揭示粘合剂涂层影响聚合物-晶体复合颗粒的机制。