Laser beam powder bed fusion and post processing of alloy 247LC

Alloy 247LC tends to crack during laser beam powder bed fusion (PBF-LB) manufacturing, requiring post-processing for crack closure. This study examines samples manufactured by PBF-LB and treated with hot isostatic pressing (HIP), HIP + solution, and aging heat treatments. Microstructural analysis reveals cracks in the as-built condition, eliminated after HIP. Bright microconstituents between cells are attributed to Hf and Ta partitioning, forming carbides. Oxides are also observed. Thermodynamic calculations indicate rapid formation of ?’ precipitates due to high Al and Ta concentrations, correlating with high hardness in the as-built condition.