کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10644895 999775 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Neutron irradiation damage of nuclear graphite studied by high-resolution transmission electron microscopy and Raman spectroscopy
ترجمه فارسی عنوان
خسارات ناشی از اشعه ی نواری از گرافیت هسته ای با میکروسکوپ الکترونی با وضوح بالا و طیف سنجی رامان
کلمات کلیدی
آسیب تابش، طیف سنجی رامان، میکروسکوپ الکترونی با وضوح بالا، مکانیزم آسیب تابش اشعه ماوراء بنفش، گرافیت هسته ای،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی انرژی هسته ای و مهندسی
چکیده انگلیسی
Nuclear graphite components are produced from polycrystalline artificial graphite manufacture from a binder and filler coke with approximately 20% porosity. During the operational lifetime, nuclear graphite moderator components are subjected to fast neutron irradiation which contributes to the change of material and physical properties such as thermal expansion co-efficient, young's modulus and dimensional change. These changes are directly driven by irradiation-induced changes to the crystal structure as reflected through the bulk microstructure. It is therefore of critical importance that these irradiation changes and there implication on component property changes are fully understood. This work examines a range of irradiated graphite samples removed from the British Experimental Pile Zero (BEPO) reactor; a low temperature, low fluence, air-cooled Materials Test Reactor which operated in the UK. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) have been employed to characterise the effect of increased irradiation fluence on graphite microstructure and understand low temperature irradiation damage processes. HRTEM confirms the structural damage of the crystal lattice caused by irradiation attributed to a high number of defects generation with the accumulation of dislocation interactions at nano-scale range. Irradiation-induced crystal defects, lattice parameters and crystallite size compared to virgin nuclear graphite are characterised using selected area diffraction (SAD) patterns in TEM and Raman Spectroscopy. The consolidated 'D'peak in the Raman spectra confirms the formation of in-plane point defects and reflected as disordered regions in the lattice. The reduced intensity and broadened peaks of 'G' and 'D' in the Raman and HRTEM results confirm the appearance of turbulence and disordering of the basal planes whilst maintaining their coherent layered graphite structure.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Nuclear Materials - Volume 467, Part 2, December 2015, Pages 557-565
نویسندگان
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