Patent Number: 060144181
Section: abstract

A fuel rod for a light water reactor comprises a cladding tube which comprises a zirconium alloy having a composition including 0.6 to 2.0% by weight of Nb, 0.5 to 1.5% by weight of Sn, 0.05 to 0.3% by weight of Fe, and the balance being Zr and incidental impurities; uranium oxide fuel pellets packed in the cladding tube; and end plugs comprising a zirconium alloy and closing both ends of the cladding tube. The cladding tube is sealed by TIG welding with the end plugs. Grain boundaries in each heat affected zone of the cladding tube, which are adjacent to a bead formed by TIG welding, have structural compositions including 4 to 30% by weight of Nb, and 0.9 to 20% by weight of Fe.