X-ray characterization of anisotropic defect formation in SiC under irradiation with applied stress

SCRIPTA MATERIALIA

卷:197

Article

Koyanagi, Takaaki¹  Sprouster, David J.²  Snead, Lance L.²  Katoh, Yutai¹ 

[1] Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN 37831 USA

[2] SUNY Stony Brook, Dept Mat Sci & Chem Engn, Stony Brook, NY 11794 USA

关键词: Silicon carbide;    Irradiation creep;    Neutron irradiation;    X-ray diffraction;   

DOI  :  10.1016/j.scriptamat.2021.113785

来源: Elsevier

【 摘 要 】

High-energy x-ray diffraction is employed to gain insight into the irradiation-induced creep behavior of silicon carbide (SiC). Polycrystalline beta-SiC specimens were simultaneously exposed to elevated temperature neutron-irradiation and mechanically applied stresses. The structural disordering was subsequently examined using two-dimensional x-ray diffraction. The intensity of the (111) shoulder peak, an indication of stacking disorder, increased when the specimens were irradiated under tensile stress. This is the first observation of nanoscale stress-induced stacking disorder in SiC at low neutron fluences. These findings suggest stress-induced preferential nucleation and/or growth of defect clusters as a key creep mechanism in neutron irradiated SiC. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free