Patent ID: 6744842
Filing Date: 2004-06-01
Classification: G21C,Y02E

Abstract:
A fuel assembly for a pressurized-water reactor, comprising:spacers having cells; control rod guide tubes; fuel rods held laterally in said cells of said spacers; a headpiece and a foot piece for fixing the fuel assembly to upper and lower core grids respectively inside a reactor pressure vessel; at least one of said spacers having a first part disposed on a radially outer side with respect to a longitudinal center axis of the fuel assembly, and a second part disposed on a radially inner side and completely surrounded by said first part; and said second part formed of Zircaloy, and said first part containing a metallic material having a lower growth in a radial direction caused by neutron radiation and a higher coefficient of thermal expansion when compared with said Zircaloy of said second part, thereby reducing expansion gaps between fuel assemblies.