The Impact of Vibrational Entropy on the Segregation of Cu to Antiphase Boundaries in Fe3Al

We performed a quantum mechanical study of segregation Cu atoms toward antiphase boundaries (APBs) in Fe3Al. The computed concentration was 3.125 at %. APBs have been characterized by shift the lattice along ?001? crystallographic direction. APB energy turns out to be lower for located directly interfaces and we found that it is equal 84 mJ/m2. Both (as point defects) extended their specific impact on local magnetic moments Fe (mostly reduction magnitude). Their combined not just simple sum effects each defect types. are predicted segregate studied APBs, but related gain very small amounts only 4 meV per atom. also phonon calculations all states with different atomic configurations mechanically stable without any soft modes. band gap frequencies Fe3Al barely affected substituents reduced APBs. contributions segregation-related changes significant, ranging from decrease 16% T = 0 K an increase 17% 400 (changes respect difference between static lattices). Importantly, examined differences entropy induced showed strongly nonlinear trends.