ZIRCALOY FUEL CLADDING TUBE, METHOD AND APPARATUS FOR SUPPRESSING CORROSION THEREOF

摘要

PURPOSE:To suppress corrosion of fuel cladding tube by forming the cladding tube of a zirconium alloy and previously coating the outer surface thereof with an oxide film. CONSTITUTION:Zircaloy is an alloy of Zr and Sn, Fe, Cr, Ni. A zircaloy fuel cladding tube is previously subjected to oxidation to coat the surface of the cladding tube with an oxide film of 0.1mum or above. For example, oxidation is carried out for about 14 hours in high temperature vapor of 363-410 deg.C under the pressure of 12+ or -0.4kg/cm2. When the film is deposited by 0.1mum or more, the surface of the cladding tube is prevented against adhesion of Cr. Since a compact black oxide film can be formed on the surface of the cladding tube, the potential of the cladding tube can be sustained at high level and corrosion of zircaloy is prevented from being accelerated by Cr.