Abstract Adhesive joints are widely developed in aeronautic and automotive design applications. When subjected to impact loading, the rate sensitivity of adhesively bonded joints becomes a subject of interest. In this study, the Mode I fracture behavior of an aeronautic adhesive is characterized. Double Cantilever Beam tests are performed under various displacement rates. A new protocol is developed to accurately measure the fracture toughness. The corrected beam theory with effective crack length is extended to measure the energy release rate during the crack growth stage. The main advantage of this new protocol is to accurately determine the crack speed without a direct experimental error. The validity of the analysis scheme is discussed considering dynamic effects. The crack speed measurement is validated by comparison to a conventional camera monitoring. The crack velocity is found to decrease with the crack length, while the fracture toughness remains unchanged.

中文翻译：

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动态载荷下粘合剂的断裂速率依赖性

摘要 粘合接头在航空和汽车设计应用中得到了广泛的发展。当受到冲击载荷时，粘接接头的速率敏感性成为一个令人感兴趣的主题。在这项研究中，表征了航空粘合剂的 I 型断裂行为。双悬臂梁测试在各种位移率下进行。开发了一种新的协议来准确测量断裂韧性。将具有有效裂纹长度的修正梁理论扩展到测量裂纹扩展阶段的能量释放率。这种新协议的主要优点是可以准确地确定破解速度，而不会产生直接的实验误差。考虑动态效应，讨论了分析方案的有效性。裂纹速度测量通过与传统摄像机监控进行比较来验证。发现裂纹速度随着裂纹长度的增加而降低，而断裂韧性保持不变。