This paper describes an innovative 3D-printed beam-based lightweight structure that is used to increase the adhesion strength of metal-composite joints without damaging the composite fibers. It is conceived as the interface between the two parts to be joined: by filling the voids of this structure with resin, a mechanical interlocking effect can be generated to enhance the mechanical properties of the junction. A dedicated design workflow was defined to explore different types of 3D beam-based structures, starting from the analysis of the main failure modes of this type of junction. Tensile tests were performed on both polymeric and metal samples to validate the effectiveness of this interlocking strategy. Results demonstrated an increase in the adhesion strength relative to standard adhesive joints. A possible practical implementation is also discussed: a new type of insert is presented for application in metal-to-polymer composite joints. Finally, such a beam-based joining approach also represents an innovative application in the field of design for additive manufacturing.

本文介绍了一种创新的基于3D打印梁的轻型结构，该结构可用于增加金属复合材料接头的粘合强度而不会损坏复合纤维。它被认为是要连接的两个零件之间的界面：通过用树脂填充该结构的空隙，可以产生机械互锁效果，以增强接合处的机械性能。定义了专门的设计工作流程，以从分析此类交界处的主要失效模式开始，探索不同类型的基于3D梁的结构。对聚合物和金属样品均进行了拉伸试验，以验证这种联锁策略的有效性。结果表明，相对于标准粘合接头，粘合强度有所提高。还讨论了可能的实际实现方式：提出了一种新型插入件，用于金属-聚合物复合材料接头。最后，这种基于梁的连接方法还代表了增材制造设计领域的创新应用。