FUEL ROD FOR LIGHT WATER REACTOR AND ITS PRODUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide fuel rods for light water reactor and its production method making possible improving corrosion resistivity and operating highly efficiently. SOLUTION: This fuel rod for light water reactor is made by charging uranium oxide fuel pellets in a clad consisting of zirconium alloy with components containing Nb:0.6 to 2.0wt.%, So:0.5 to 1.5wt.%, Fe:0.05 to 0.3wt.% and Zr and unavoidable impurity for the rest. Both ends of the clad are sealed with end plugs of zirconium alloy which are TIG-welded to the clad for sealing. In this case, the component of the grain boundary in the structure at the heat affected zone of the clad adjacent to bead formed by TIG-welding between the clad and the end plugs is controlled to contain Nb:4 to 30wt.% and Fe:0.9 to 20wt.%.