کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9837609 1525281 2005 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Atomic states, potential energies, volumes, stability and brittleness of ordered FCC Ti3Al-type alloys
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Atomic states, potential energies, volumes, stability and brittleness of ordered FCC Ti3Al-type alloys
چکیده انگلیسی
According to the basic information of sequences of characteristic atoms in the FCC Ti-Al system, the compositional variations of the atomic states, atomic potential energies, atomic volumes, lattice constants and cohesive energies of the ordered FCC Ti3Al-type alloys have been calculated. Without considering the influence of the second nearest neighbouring atoms, the D022- and L12-Ti3Al compounds have the same atomic state, same atomic volume, same lattice constant and same cohesive energy. Their average atomic state is 0.75[Ar](3dn)0.229(3dc)2.5669(4sc)0.5448(4sf)0.6593 +0.25[Ne](3sc)1.772(3pc)1.008(3sf)0.22. Considering the influence of second neighbouring atoms, the calculated atomic potential energies, formation energies and lattice constants of the D022- and L12-Ti3Al compounds are, respectively, εa=-4.8158eV/atom, ΔH=−0.3378 eV/atom, a=0.39131 nm, c=0.44108 nm, c/a=1.1272; and εa=−4.7952 eV/atom, ΔH=−0.3172 eV/atom, a=0.41091 nm. The D022-Ti3Al compound is slightly more stable than the L12- Ti3Al compound. The correctness of these results has been proved indirectly by the calculated results of the D022- and L12-TiAl3 as well as HfGa2- and ZrGa2-type TiAl2 compounds with the same basic information and the same method. Between 0 and 40 at.%Al, the HCP lattice is more stable than the FCC lattice, for which the atomic state factor may play determining action. The brittleness order of these compounds is L12-Ti3Al
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica B: Condensed Matter - Volume 362, Issues 1–4, 15 May 2005, Pages 1-17
نویسندگان
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