Materials and Processes for CANDU Fuel Fabrication

Abstract

CANDU Fuel Fabrication comprises the preparation of high density naturally enriched UO₂ pellets, hermetic encapsulation of the pellets in zirconium alloy tubes and final assembly of the subassemblies in a suitable thermal-hydraulic array. The various processes used in the fabrication of the fuel are described with emphasis on the properties of the raw materials that are important for successful manufacture and end use. Specifically this includes consideration of the importance of controlling the physical properties of both the ceramic grade UO₂ powder used for pellet fabrication and of the thin wall Zircaloy-4 alloy tubing used for fuel element manufacture.