Fabrication of Zircaloy-4 Fuel Cladding Pipe with Nanostructured Oxide Layer for Prevention of Hydrogen Production

There has been an attempt to protect zircaloy fuel cladding by coating SiC. Research on producing oxide layer that can block fuel cladding from water on the surface of zircaloy fuel cladding by means of anodizing to reduce the rate of oxidation of fuel cladding at Loss Of Coolant Accident (LOCA) is an significant ongoing study subject. Applying nanostructured oxide layer to the prevention of thermal deformation of oxide layer was already suggested in our research group, the reasons of which is nanoporous structure is better than nanotube structure in terms of corrosion-resistant structure because nanotube structure can be easily peeled off. In this study, methods which are able to control morphology between nanoporous and nanotube structure were conducted by changing the anodizing conditions. Hence, Using glycerol and ammonium fluoride, Zircaloy-4 was anodized by varying water contents and applied voltage. Zircaloy-4 pipe with nanostructured surface was fabricated by anodization technique. The produced nanostructure is quite even but the thickness of the oxide layer is not even. The nanostructured surface can increase the thermal characteristics of the zircaloy-4 fuel cladding