Microscopic phase-field modeling of atomic anti-site behaviors in
precipitation progress of Ni3(AlFe)
precipitation progress of Ni3(AlFe)
(1. School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. School of Materials Science and Engineering, North University of China, Taiyuan 030051, China;
3. School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China)
2. School of Materials Science and Engineering, North University of China, Taiyuan 030051, China;
3. School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China)
Abstract: The effects of temperature on atomic anti-site behaviors in L12-Ni3(AlFe) phases were studied using microscopic phase-field dynamic model in precipitation progress of Ni75Al20Fe5 alloy. The results show that with the increase of temperature, the formation of NiAl and AlNi anti-sites is much easier in Ni3(AlFe), and Ni and Al anti-site atoms show clearly stronger temperature-dependent than Fe anti-site atoms. The evolution progress of anti-site atoms is completed at the initial growth stage of L12-Ni3(AlFe) phases. The site occupation probabilities of Ni atoms on the sublattice A (NiNi, face centers sites of FCC), and Al and Fe atoms on the sublattice B (AlAl and FeAl, corners sites of FCC) all present the degressive tendency with the temperature increasing. Fe atoms mainly prefer to occupy the Al sublattice at the whole temperature range.
Key words: anti-site; microscopic phase-field; precipitation; Ni3(AlFe)