Committee V.3: Materials and Fabrication Technology

Abstract

Committee Mandate The committee shall give an overview of current developments in materials and fabrication technologies, and identify knowledge gaps, give recommendations on how to improve design, qualification and approval processes in order to keep pace with upcoming innovations. Further, the Committee shall raise the awareness on challenges from new materials, fabrication processes and increased digitization with respect to structural reliability as well as sustainable benefits. Introduction This report presents recent developments in materials and fabrication technology in the shipping and offshore fields. The current situation in maritime trading is very uncertain with strong disturbances in the container traffic, however at least for 2020, the shipbuilding industry seems, overall, to recover from previous dips, like in 2016. There is a strong development and qualification of new materials, i.e., composites, and processes like additive manufacturing. But mainly there is a strong movement towards digitalization of the ship building industry, i.e., moving towards industry 4.0. Chapter 2 shows recent trends in ship and offshore production, and some national and international research projects in these fields, primarily publicly funded. The development of new metallic materials and composites are dealt with in Chapter 3. Chapter 4 gives an overview of welding methods for steels, fabrication of bi-metallic joints, and metal / composite joints, coatings and recent development s in additive manufacturing in particular WAAM methods. Qualification and approval of new materials and processes, monitoring of new processes and standards for hull construction are discussed in Chapter 5. Chapter 6 describes the development of a digital shipyard, including Digital twins, discrete element simulations and augmented reality. Recent development of simulating mechanical effects of fabrication, and method to mitigate welding deformations are discussed in Chapter 7. Chapter 8 describes two benchmarks, the first deals with the load capacity of sandwich panels with a foam core. This has relevance when approving new materials for ship hulls. We give recommendations on what tests that need to be carried out to show the full load capacity of such a panel. The second benchmark deals with residual deformations when welding a stiffener to a plate. This has relevance when fabricating and assembling larger structures consisting of stiffened plates. It is found that it may be difficult to simulate this process and much consideration must be given to the experimental situation and material modelling to give acceptable results. The benchmarks are presented in detail in Appendices A and B. Finally, Chapter 9 summarizes the report and gives recommendations.