Inspection of irradiated P-7 fuel tubes

Mark 16 U-A1 alloy production fuel tubes and six special U3O8-A1 powder metallurgy (PM) test assemblies were successfully irradiated in P-7 reactor charge beginning December 1976. A year after irradiation, the outer surfaces were inspected under water in P-Area basin. Inspection showed that a ''black'' oxide had formed on the bottom ∼2/3 and flaked off in some areas for both the production and PM tubes. A small cladding defect was also observed on one PM outer tube near the bottom. Sections were cut from the tubes and metallographically examined in the SRL High Level Caves (HLC). This report gives results of the examinations. 8 refs., 9 figs., 1 tab