Welding of high-resilience martensitic stainless steel for hydrodynamic components in innovative seacraft: a comparison of traditional and HDE technologies

For the designer, the production of innovative seacraft involves the use of atypical materials at the shipyard. This article presents a comparison between traditional (SMAW) and innovative [LBW, electron beam welding (EBW)] welding technologies to illustrate the feasibility and suitability – also in economic terms – of the penetration of new welding technologies in the shipbuilding sector. In particular, the material considered for the production of submerged bearing components in an innovative submerged-wing hydrofoil is X4CrNiMo13-4, a martensitic stainless steel presenting improved resilience chosen by the shipbuilding company (Rodriquez Cantieri Navali), above all, on account of its high mechanical strength. In order to avoid costly PWHT, which, given the large size of the components, has a heavy influence on production costs, welding procedure specifications were developed using an austenitic filler material that, while inducing a limited reduction in performance in the melt zone, allows for conspicu...