Significantly enhanced creep resistance in Ni-based superalloy by 3D-printed cellular structure

High resistance to creep is important for superalloys because it is usually used for manufacturing hot-end parts of aeroengines. This work shows that the GH3536 – a Ni-based superalloy – with a cellular structure produced during 3D printing presents a quite high strength and creep resistance, compared to the samples without cells, such as wrought samples. The cellular structure in 3D-printed GH3536 can effectively hinder dislocation slip during plastic deformation, and induce to form new sub-cells within the original cells during creep, contributing to stronger obstacles to dislocation motion. As a result, 3D-printed GH3536 exhibits not only a high yield strength ∼16 % higher than that of the wrought sample, but also an excellent creep resistance with a small creep rupture strain and a long creep life, which is nearly twice that of the wrought sample. These results suggest that 3D printing is a promising method to manufacture a high-strength and creep-resistant GH3536 alloy, and our work opens new avenues for improving the high-temperature performance of solid solution strengthened superalloys by designing the substructure within grains.