Scanning electron microscopy and atom probe tomography characterization of laser powder bed fusion precipitation strengthening nickel-based superalloy.

Atom probe tomography (APT) was utilized to supplement scanning electron microscopy (SEM) characterization of a precipitation strengthening nickel-based superalloy, Alloy 247LC, processed by laser powder bed fusion (L-PBF). It was observed that the material in the as-built condition had a relatively high strength. Using both SEM and APT, it was concluded that the high strength was not attributed to the typical precipitation strengthening effect of γ'.

Influence of Laser Powder Bed Fusion Process Parameters on Voids, Cracks, and Microhardness of Nickel-Based Superalloy Alloy 247LC.

The manufacturing of parts from nickel-based superalloy Alloy 247LC by laser powder bed fusion (L-PBF) is challenging, primarily owing to the alloy's susceptibility to cracks. Apart from the cracks, voids created during the L-PBF process should also be minimized to produce dense parts. In this study, samples of Alloy 247LC were manufactured by L-PBF, several of which could be produced with voids and crack density close to zero.