Influence of Scan Strategies in Electron Beam Powder Bed Fusion on Solidification, Microstructure, and High‐Temperature Compressive Properties of γ′‐Strengthened Inconel 738LC

Processing refractory and crack‐prone alloys remains challenging in additive manufacturing. However, this limitation can be overcome using powder bed fusion with an electron beam (PBF‐EB/M), thanks to its inherently high process temperatures and reduced thermal gradients. This study investigates the PBF‐EB/M process for the γ′‐strengthened nickel‐base superalloy Inconel 738LC, which is conventionally categorized as nonweldable, both experimentally and by thermophysical simulation. Different line and spot scanning strategies are employed to reveal their effect on thermal profiles during solidification and the resulting microstructures in as‐built and heat‐treated conditions. The strength of the samples is tested in compression up to 1100°C. Samples processed using PBF‐EB/M are observed to be crack‐free with relative densities up to 99.9%. Depending on the scanning strategy applied, the microstructure ranges from nearly equiaxed to highly textured, with large epitaxially grown columnar grains. Initial solidification conditions influence the size and morphology of both MC‐type carbides and γ′ phases, and spot‐melted samples show a bimodal γ′ distribution after heat treatment. At intermediate temperatures, spot‐melted samples in the as‐built condition demonstrate higher compressive strength than line‐scanned counterparts. These results highlight the effectiveness of process‐driven control of microstructural kinetics in PBF‐EB/M for optimizing the mechanical performance of γ′‐precipitation strengthened materials.