Determination of neutron irradiation temperatures of SiC using electrical resistivity method

JOURNAL OF NUCLEAR MATERIALS

卷:540

Article

Wang, Hsin¹  Koyanagi, Takaaki¹  Geringer, Josina W.¹  Campbell, Anne A.¹  Katoh, Yutai¹ 

[1] Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN 37830 USA

关键词: SiC;    Electrical resistivity;    Neutron irradiation;    Irradiation temperature;   

DOI  :  10.1016/j.jnucmat.2020.152370

来源: Elsevier

【 摘 要 】

The irradiation temperature of silicon carbide (SiC) was determined post-irradiation by examination of the recovery of the electrical resistivity due to thermal annealing in a rapid heating/cooling optical furnace. High-purity, high-resistivity grade SiC is routinely used as a passive temperature monitor in neutron irradiation studies at the High Flux Isotope Reactor (HFIR), and this paper presents an alternative automated technique for determination of the irradiation temperature the SiC experienced. Neutron collisions with the atoms results in displaced lattice atoms (interstitials) that act as electron donors yielding a significant decrease in electrical resistivity. The irradiation defects become thermodynamically unstable and start to recombine, when annealed above the irradiation temperature, resulting in a recovery of the electrical resistivity. The resistivity is measured at a fixed elevated temperature above ambient, which is below the target irradiation temperature. When the resistivity is plotted as a function of annealing temperatures, a clear increase is observed due to the recovery of irradiation defects. We have demonstrated that this electrical resistivity measurement of SiC is effective to determine irradiation temperature of SiC. Energy levels of various defects in SiC were calculated from Arrhenius plots of electrical conductivity versus inverse temperature. (C) 2020 Elsevier B.V. All rights reserved.

【 授权许可】

Free