skip to main content

Title: Stability of SiC-Matrix Microencapsulated Fuel Constituents at Relevant LWR Conditions

This paper addresses certain key feasibility issues facing the application of SiC-matrix microencapsulated fuels for light water reactor application. Issues addressed are the irradiation stability of the SiC-based nano-powder ceramic matrix under LWR-relevant irradiation conditions, the presence or extent of reaction of the SiC matrix with zirconium-based cladding, the stability of the inner and outer pyrolytic graphite layers of the microencapsulated (TRISO) particle at this uncharacteristically low irradiation temperature, and the state of the particle-matrix interface following irradiation which could possibly effect thermal transport. In the process of determining these feasibility issues microstructural evolution and change in dimension and thermal conductivity was studied. As a general finding the SiC matrix was found to be quite stable with behavior similar to that of CVD SiC. In magnitude the irradiation-induced swelling of the matrix material was slightly higher and irradiation-degraded thermal conductivity was slightly lower as compared to CVD SiC. No significant reaction of this SiC-based nano-powder ceramic matrix material with Zircaloy was observed. Irradiation of the TRISO in the 320-360 C range to a maximum dose of 7.7 1025 n/m2 (E > 0.1 MeV) did not have significant negative impact on the constituent layers of the TRISO fuel. At the highestmore » dose studied layer structure and interface integrity remained essentially unchanged with good apparent thermal transport through the microsphere to the surrounding matrix.« less
 [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1]
  1. ORNL
Publication Date:
OSTI Identifier:
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Nuclear Materials; Journal Volume: 448
Research Org:
Oak Ridge National Laboratory (ORNL); High Flux Isotope Reactor (HFIR); High Temperature Materials Laboratory (HTML)
Sponsoring Org:
NE USDOE - Office of Nuclear Energy
Country of Publication:
United States
nuclear fuel; SiC