Comparative analysis of cavitation erosion behavior in wire-arc directed energy deposition and cast nickel-aluminum bronze alloys

Abstract

In this study, the cavitation erosion (CE) behavior of wire-arc directed energy deposition (DED) nickel-aluminum bronze (NAB) alloys is compared with that of cast alloys, and the synergistic effect between corrosion and CE is investigated. The CE resistance of the wire-arc DED NAB alloy is better than that of the cast alloys. The CE of NAB alloys preferentially occurs at the boundaries of the α-Cu and residual β phases, and in the matrix around the κ phase. The residual β phase exhibits greater damage than the α-Cu phase. Throughout the CE, the alloys are dominated by local corrosion characteristics (selective-phase corrosion), while the wire-arc DED NAB alloys exhibit superior uniform corrosion characteristics. Notably, the uniform corrosion characteristics of all alloys are enhanced after CE. The mass loss caused by the synergistic effect of the cast NAB alloy and wire arc DED NAB alloy accounts for 56% and 52% of the total mass loss, with the corrosion-induced CE increment exceeding that of the CE-induced corrosion increment.