کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7985918 | 1515103 | 2018 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Three-dimensional scanning transmission electron microscopy of dislocation loops in tungsten
ترجمه فارسی عنوان
میکروسکوپ الکترونی سه بعدی انتقال اسکن از حلقه های ناپیدا در تنگستن
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
ساقه، متالورژی، جابجایی، تصویربرداری استریو،
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
دانش مواد (عمومی)
چکیده انگلیسی
Scanning transmission electron microscopy (STEM) imaging using diffraction contrast is a powerful technique to assess crystal defects. In this work it is used to assess the spatial distribution of radiation induced defect in tungsten. In effect, its irradiation leads to the formation of nanometric dislocation loops that under certain conditions may form intriguing 3-D rafts. In this study, we have irradiated thin tungsten samples in situ in a TEM with 1.2â¯MeVâ¯W ions to 0.017 dpa at room temperature (RT) and at 700â¯Â°C. Besides the Burgers vector analysis, the number density and size of the dislocation loops with their spatial arrangement were quantitatively characterized by stereo imaging in STEM mode. Most of the loops have a Burgers vector ½ a0 ã111ã, with some a0 ã100ã at room temperature. Loops are located mainly in the simulated damage profile but there is also a significant portion in deeper regions of the sample, indicating that loops in W diffuse easily, even at RT. At 700â¯Â°C, loops form elongated rafts that contain dislocation segments having a Burgers vector ½ a0 ã111ã. The rafts are narrow and reside on {111} planes; they are elongated along ã110ã directions, which correspond, when combined to the rafts' Burgers vector, to the lines of edge dislocations. Compared to conventional TEM, 3-D analysis in STEM appears thus as a powerful technique for quantitative analyses of defects in tungsten, as it allows reducing the background diffraction contrast and reaching thicker areas of the electron transparent foil, here 0.5â¯Î¼m of tungsten at 200â¯kV.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Micron - Volume 113, October 2018, Pages 24-33
Journal: Micron - Volume 113, October 2018, Pages 24-33
نویسندگان
S. Hasanzadeh, R. Schäublin, B. Décamps, V. Rousson, E. Autissier, M.F. Barthe, C. Hébert,