Fatigue response of wire-arc additive manufactured nickel-aluminum bronze (NAB) in the post-annealed condition

Abstract

Nickel-aluminum bronze (NAB) is chosen for critical applications like marine propellers, pump components, and offshore structures due to its exceptional mechanical properties and corrosion resistance. Considering the utmost importance of the fatigue performance of NAB in such applications, this study investigates the fatigue performance of wire arc additive manufactured (WAAM) NAB in the annealed (675 °C for 6 h then furnace cooling) condition. To this end, static mechanical properties were evaluated using uniaxial tensile testing, while fatigue properties were assessed through fully reversed tests conducted at ambient temperature. Electron backscatter diffraction (EBSD) was utilized for the examination of the texture, and grain size distribution in annealed WAAM NAB. Additionally, scanning electron microscopy was employed to inspect fatigue-fractured specimens, while the analysis of EBSD was conducted to examine the deformation behavior beneath the crack initiation zone. The results provide insights into the fatigue life, crack initiation, and propagation characteristics of WAAM NAB relative to the cast counter material. The findings of this research provide valuable insights into the mechanical properties, microstructural characteristics, and fatigue response of WAAM NAB, informing the design of fatigue-resistant components and supporting the reliable utilization of WAAM NAB in demanding applications such as the marine and naval industries.