The role of "process control" and "inspection" steps in the quality assurance of SS 316 clad mixed plutonium-uranium carbide fuel pins for FBTR

Abstract

"Process Control" and "Inspection" steps played a dominant role in the fabrication of stainless steel (SS) 316 clad hyperstoichiometric (Pu_0.7U_0.3)C driver fuel pins for the 42.5 MWt fast breeder test reactor (FBTR) at Kalpakkam. The mixed carbide fuel was fabricated in the Radiometallurgy Division (RMD) of the Bhabha Atomic Research Centre (BARC) involving the following principal process steps: vacuum carbothermic reduction of UO₂, PuO₂ and graphite powder-mixture; crushing and milling of carbide clinkers followed by cold-pelletisation and sintering; encapsulation of carbide fuel pellets in SS 316 cladding tube. The role of "Process Control" and "Inspection" steps in the fabrication campaign of mixed carbide fuel for FBTR is summarized, high-lighting the equipment utilised and the techniques developed for monitoring the starting materials, the process intermediates and the final product.