Place: EUROMAT 2019 Stockholm, Sweden
Erik Bitzek, Department of Materials Science and Engineering, Department of Materials Science and Engineering Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
Introduction/Purpose Hydrogen enhanced decohesion is expected to play a major role in ferritic steels, especially at grain boundaries. We address the effects of some common interstitial and substitutional alloying elements on the H segregation behaviour and decohesion at special grain boundaries (GB) in body-centered cubic iron, and discuss the impact for multiscale mechanical and thermodynamic modelling. Methods Spin polarized density functional theory calculations are used to determine the ideal segregation sites, segregation energies, and key mechanical properties such as the work of separation and fracture stress of the GB. These quantities are used as input for thermodynamic and mechanical modelling.