A Comparative Life Cycle Assessment of Structural Solutions Using Dissimilar Materials and Hybrid Joints

In this work, a Life Cycle approach is implemented to compare the environmental performances of innovative technologies such as dissimilar joints, hybrid metal-composite joints, and additive manufactured (AM) components. The study is part of a broader project whose goal is to develop solutions that improve the performance and durability of components and reduce their environmental impact throughout the life cycle, promoting circular economy principles, recyclability, and the production of sustainable structures. For dissimilar joints, the use of AM is particularly promising as it can improve the sustainability and circularity of manufacturing processes. AM has already shown great potential, though significant work is needed to meet the performance standards of the industry. In the case of hybrid joints, the goal is to combine different materials to create stronger, more durable composites that can improve the reliability of structural ship details. This approach supports the circularity of the shipyards supply chain, which is increasingly focused on lightweight materials to boost efficiency and reduce carbon emissions. The main objective of the study is to establish a robust basis for decision making and guide the design of components that must perform well both in terms of mechanical properties and environmental performance. The scenarios to be compared concern components fulfilling the same structural function, but produced using different materials and joining techniques; specifically, scenarios will include cases with traditional materials (e.g., welded steel joints), cases with dissimilar joints realized using different innovative techniques, with base materials manufactured through various processes (including additive manufacturing), and hybrid components.