High-temperature creep-induced site occupation evolution in the γ′ lattice in a Ru-bearing Ni-based superalloy

oleh: Yunsong Zhao, Na Li, Li Wang, Junyang He, Weihong Liu, Min Song

Format: Article
Diterbitkan: Taylor & Francis Group 2023-10-01

Deskripsi

By using state-of-the-art characterisation techniques including atom probe tomography and atomic resolved elemental mapping, we successfully probed the site occupation evolution associated with composition change in γ′, during 1100°C creep of a fourth generation Ru-bearing Ni-based superalloy. It is quantified that, W and Ru maintain unchanged site preference after creep rupture, while interestingly, the rest elements especially Co, Ta and Re show a weakened preference at both α- and β-sites in the γ′ lattice. This indicates the overall reduced γ′ ordering degree and thus the possible decrease in planar fault energies, which further facilitates dislocation shearing in γ′.