Abstract The fracture toughness and fracture process of second generation acrylic (SGA) adhesive joints were investigated in detail using tapered double cantilever beam (TDCB) tests. The distribution of granular elastomer with a size of ca. 150 nm in the bulk specimen by transmission electron microscopy (TEM) observation was similar to the distribution of cavitation determined by scanning electron microscopy (SEM) observation of the fracture surface. A mechanism was proposed for the role of the elastomer and acrylic phase in the cohesive failure process of SGA. A dimple, which is evidence of ductile fracture, was observed on the fracture surface. The relationships between the size of dimples, their number and energy release rate were clarified. An understanding of the proposed failure mechanisms is useful for constructing a numerical model for stress analysis and explaining the fracture phenomenon.

中文翻译：

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SGA胶接缝裂纹扩展机制

摘要 采用锥形双悬臂梁（TDCB）试验详细研究了第二代丙烯酸（SGA）胶接接头的断裂韧性和断裂过程。尺寸为约的粒状弹性体的分布。150 nm 的大块试样通过透射电子显微镜 (TEM) 观察与通过扫描电子显微镜 (SEM) 观察断口确定的空化分布相似。针对弹性体和丙烯酸相在 SGA 内聚破坏过程中的作用提出了一种机制。在断裂表面上观察到凹痕，这是韧性断裂的证据。阐明了凹坑的大小、它们的数量和能量释放率之间的关系。