Healing stacking fault tetrahedron in NiFe solid solution alloys through grain boundary migration

J Li and XH Yang and P Wang and QL An, JOURNAL OF NUCLEAR MATERIALS, 565, 153738 (2022).

DOI: 10.1016/j.jnucmat.2022.153738

A stacking fault tetrahedron (SFT) is a very common kind of defects in face-centered cubic metals under irradiation environment. The grain boundary (GB) migration can effectively heal the SFT through the GBSFT interaction to improve the irradiation resistance of materials. In this study, the GB-SFT interactions in pure Ni and NiFe bicrystals subjected to shear loading were investigated by the molecular dynamics simulations. After the GB-SFT interaction, the GB in pure Ni is pinned, and a void appears as it migrates further, but the GB in NiFe solid solution alloys still remains flat. The migrating GB in the alloys has a higher efficiency to heal the SFT than that in pure Ni. The GB roughening caused by the alloying element brings more transitional structural units into the GB to accommodate more vacancies. As a result, similar to elevated temperature, increasing Fe atom concentration could improve the capacity of GB to heal the SFT.(c) 2022 Elsevier B.V. All rights reserved.

Return to Publications page