Synchronously enhanced printability and properties of additively manufactured nickel-based superalloys via alloying minor Sc

As major forming elements of γ′ strengthening phase, Al and Ti are critical for achieving superior properties of Ni-based superalloy. However, Al + Ti over 6 wt% leads to poor printability and cracking during additive manufacturing. In this work, the printability and properties of a nickel-based superalloy with Al + Ti reaching 7 wt% is synchronously improved via alloying minor Sc, the mechanism behind that is revealed by investigating the effects of Sc on the grain size, precipitation, and tensile fracture behavior of that nickel-based superalloy. This work provides a promising alternative method for optimizing the performance of superalloys prepared by additive manufacturing.