Triple Junction Segregation Dominates the Stability of Nanocrystalline Alloys.

ABSTRACT: We present large-scale atomistic simulations that reveal triple junction (TJ) segregation in Pt-Au nanocrystalline alloys in agreement with experimental observations. While existing studies suggest grain boundary solute segregation as a route to thermally stabilize nanocrystalline materials with respect to grain coarsening, here we quantitatively show that it is specifically the segregation to TJs that dominates the observed stability of these alloys. Our results reveal that doping the TJs renders them immobile, thereby locking the grain boundary network and hindering its evolution. In dilute alloys, it is shown that grain boundary and TJ segregation are not as effective in mitigating grain coarsening, as the solute content is not sufficient to dope and pin all grain boundaries and TJs. Ou

SUBMITTER: Barnett AK 

PROVIDER: S-EPMC11311549 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature