Abstract
Raman spectra from polycrystalline beta-silicon carbide (SiC) were collected following neutron irradiation at 380–1180 °C to 0.011–1.87 displacement per atom. The longitudinal optical (LO) peak shifted to a lower frequency and broadened as a result of the irradiation. The changes observed in the LO phonon line shape and position in neutron-irradiated SiC are explained by a combination of changes in the lattice constant and Young's modulus, and the phonon confinement effect. The phonon confinement model reasonably estimates the defect-defect distance in the irradiated SiC, which is consistent with results from previous experimental studies and simulations.
Original language | English |
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Pages (from-to) | 58-62 |
Number of pages | 5 |
Journal | Scripta Materialia |
Volume | 125 |
DOIs | |
State | Published - Dec 1 2016 |
Funding
This work is supported by the U.S. Department of Energy (DOE), Office of Fusion Energy Sciences and Office of Nuclear Energy for the Fuel Cycle Research & Development program under contact DE-AC05-00OR22725 with Oak Ridge National Laboratory managed by UT-Battelle, LLC. The research is also supported in part by the High Flux Isotope Reactor, which is sponsored by the DOE Office of Basic Energy Sciences. The authors are grateful to A. A. Campbell and J. Nanda (ORNL) for their valuable comments. The XRD experiment shown in this paper was carried out at the National Synchrotron Light Source-II at Brookhaven National Laboratory (BNL), which is supported by the U.S. DOE. The authors would like to thank D. Sprouster and L. Ecker (BNL) for their invaluable efforts and time given to the XRD experiment and the analysis.
Keywords
- Irradiation defects
- Raman spectroscopy
- Silicon carbide