Initial Post Irradiation Examination Data for PCEA Graphite Irradiated at 900C in HFIR

Abstract

Twelve PCEA graphite specimens (rectangular section bars, 6 x 6 x 50 mm) were successfully irradiated in rabbit capsules in the target region of the High Flux Isotope Reactor (HFIR) at ORNL. Six of the specimens attained a dose of 6.61 displacements per atom (dpa) at a design temperature of 900°C and the remaining 6 specimens attained a dose of 10.16 dpa at 900°C. Because of the high dose received by the specimen’s, loose surface contamination was a problem and thus post irradiation examination (PIE) was conducted in glove bags to minimize risk of contamination spread. The specimens were examined to determine their irradiation induced dimensional changes, and changes in dynamic flexural Young’s modulus (fundamental frequency method), longitudinal dynamic Young’s modulus, dynamic shear modulus, and Poisson’s ratio (sonic velocity method), and electrical resistivity The results of our PIE are reported and analyzed here in comparison to historic graphite data.