کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1687028 | 1010637 | 2009 | 4 صفحه PDF | دانلود رایگان |
Using a first-principles method based on density functional theory, we have investigated energetics and site preference of helium (He) in a ferromagnetic bcc-iron (Fe) ∑5(310)/[001] grain boundary (GB). We calculate the binding energies of He atom in the GB, which show that the substitutional He is energetically favored in comparison with the interstitial He with a small energy difference of 0.06 eV. The segregation energy is calculated to be ∼1.4 eV for the energetically favorable GB substitutional and interstitial sites, which is large enough for the He atoms to segregate to these sites, independent of the temperature and the bulk He concentration. This leads to the conclusion that all the He atoms will segregate into the GB at a typical temperature range of 573–1173 K.
Journal: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms - Volume 267, Issue 18, 15 September 2009, Pages 3200–3203