Corrosion and Fatigue Behavior of Boeing Space, Intelligence, and Weapons Systems Laser Powder Fusion Built Scalmalloy® in 5% NaCl

ABSTRACT This paper presents the results of a preliminary investigation into the corrosion resistance of laser powder bed fusion (LPBF)‐produced Scalmalloy® specimens built by Boeing Space, Intelligence, and Weapons Systems (BSI&WS). The specimens were first exposed to a 5% NaCl salt fog test at 35°C, and a comparison was made with prior tests on the aluminum alloy AA7050‐T7451. The AA7050‐T7451 alloy was chosen since it is widely used in fixed‐wing aircraft, rotary‐wing aircraft, and in space structures. This preliminary study reveals that BSI&WS LPBF‐built Scalmalloy® is significantly more resistant to corrosion pitting than AA7050‐T7451. These prior exposed (Scalmalloy®) specimens were then fatigued tested, and it was shown that exposure for 28 days to a 5% salt spray fog environment at 35°C did not reduce the durability of the specimens. As such, this study, when taken in conjunction with the authors' previous report on the exceptional damage tolerance of Scalmalloy®, reveals that the BIS&WS LPBF Scalmalloy® is particularly attractive for use on a range of both fixed‐ and rotary‐wing military aircraft. It also reinforces the potential for BSI&WS LPBF Scalmalloy® to be used in building parts for attritable aircraft/drones.