Patent Number: 047284889
Section: claims

1. In a water reactor operating environment, the combination having improved fretting wear resistance comprising: an elongated tubular water displacer rod; having a low neutron absorption cross section  guide support plates distributed along the length of said water displacer rod;  said water displacer rod intersecting said guide support plates through apertures in said guide support plates;  said water displacer rod having a plurality of spaced apart annular electrospark deposited coatings, each said coating facing the wall of a respective said aperture, said electrospark deposited coatings comprising Cr.sub.2 C.sub.3 ;  wherein said water displacer rod has a tube wall composed of a zirconium base alloy;  and wherein said guide support plates are composed of a stainless steel alloy.  a second electrospark deposited coating metallurgically bonded to said walls of said apertures. 2. The combination according to claim 1 further comprising: 3. The combination according to claim 1 wherein said coating is about 0.001 to about 0.002 inches thick. 4. The combination according to claim 1 wherein said zirconium base alloy is selected from the group consisting of Zircaloy-2, Zircaloy-4 and zirconium-niobium alloys.