Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Neutron displacement damage cross-sections for SiC

Technical Report ·
OSTI ID:139203
;  [1]
  1. Univ. of California, Los Angeles (United States)
The objective of the present study is to develop and apply a computational tool for calculations of neutron displacement cross-sections for SiC in various fission and fusion neutron spectra. Calculations of neutron displacement damage cross-sections for SiC are presented. Biersack and Haggmark`s empirical formula is used in constructing the electronic stopping power, which combines the Lindhard`s model at low PKA energies and the Bethe-Bloch`s model at high PKA energies. The electronic stopping power for polyatomic materials is computed on the basis of Bragg`s Additivity Rule. A continuous form of the inverse power law potential is used for nuclear scattering. Coupled intergro- differential equations for the number of displaced atoms j, caused by PKA i, are then derived. The procedure outlined above gives partial displacement cross-sections, displacement cross-sections for each species of the lattice, and for each PKA type. The corresponding damage rates for several fusion and fission neutron spectra are calculated. The stoichiometry of the irradiated material is investigated by finding the ratio of displacements among various atomic species. The role of each specie in displacing atoms is also investigated by calculating the fraction of displacements caused by each PKA type. The study shows that neutron displacement damage rates of SiC in typical magnetic fusion reactor first walls will be {approximately}10-15 [dpa][MW]{sup {minus}1}[m]{sup 2}, that in typical lead-protected inertial confinement fusion reactor first walls to be {approximately}15-20 [dpa][MW]{sup {minus}1}[m]{sup 2}. For fission spectra, the neutron displacement damage rate of SiC is {approximately}74[dpa]per 10{sup 27}n/m{sup 2} in FFTF, {approximately}39[dpa]per 10{sup 27} in HFIR, and 25 [dpa] per 10{sup 27} in NRU. Approximately 80% of displacement atoms are shown to be of the carbon-type.
Research Organization:
Oak Ridge National Lab., TN (United States)
OSTI ID:
139203
Report Number(s):
DOE/ER--0313/13; ORNL/M--2722; ON: DE93013462
Country of Publication:
United States
Language:
English