Abstract The potential to improve the mechanical properties of adhesive joints via micro-structured interlocking features is investigated. The micro-structured surfaces were fabricated in polycarbonate via injection moulding from a master template. The specimens were then bonded in an interlocking configuration to form single lap joints and tested to failure in tension. Planar untreated (i.e. un-abraded) and planar roughened (i.e. abraded) samples were also tested to provide benchmarks. Compared to the planar roughened case, results show that micro-structuring the interface can yield up to a 95.9% increase in strength and up to 162% increase in work to failure. Increases in strength and work to failure beyond the planar roughened level are attributed to mechanical interlocking of features. As deformation proceeds, progressive bending of each pair of interlocking features develops an increasing resistive load which allows the total load to significantly exceed that of the planar roughened case. Work to failure is increased via a combination of increased maximum force, increased displacement enabled by microfeature bending and a more torturous crack path. Low clearances between interlocking features were found to be favourable for mechanical properties owing to reduced bending stiffness of the repeating periodic unit at the interface.

中文翻译：

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通过微结构机械互锁提高粘合接头的强度和韧性

摘要 研究了通过微结构互锁特征改善胶接接头机械性能的潜力。微结构表面是通过从主模板注塑成型的聚碳酸酯制成的。然后将样品以互锁配置粘合以形成单搭接接头并测试拉伸失效。还测试了平面未处理（即未研磨）和平面粗糙化（即研磨）样品以提供基准。与平面粗糙的情况相比，结果表明，界面的微结构可以使强度增加高达 95.9%，失效功增加高达 162%。超出平面粗糙水平的强度增加和失效功归因于特征的机械互锁。随着变形的进行，每对互锁特征的渐进弯曲会产生增加的电阻负载，这使得总负载显着超过平面粗糙外壳的负载。最大力的增加、微观特征弯曲导致的位移增加以及更曲折的裂纹路径相结合，从而增加了失效功。由于界面处重复周期单元的弯曲刚度降低，因此发现互锁特征之间的低间隙有利于机械性能。