Nuclear fuel rod for fast reactors including metallic fuel slug coated with protective coating layer and fabrication method thereof

Abstract

Provided are a nuclear fuel rod for fast reactors that includes a metallic fuel slug coated with a protective coating layer and a fabrication method thereof. The nuclear fuel rod for fast reactors that includes a surface treated metallic fuel slug and a cladding tube according to the present invention has an excellent effect of stabilizing components of the metallic fuel slug and fission products or impurities, because the interdiffusion between the metallic fuel slug and the cladding tube does not occur. Also, since the uniform coating on the surface of the metallic fuel slug may be facilitated and fabrication costs may be significantly reduced in comparison to a typical technique of using a functional material for preventing the interdiffusion at an inner surface of the cladding tube, it may be suitable for fabricating the nuclear fuel rod for fast reactors.

What is claimed is: 
     
         1 . A fast reactor nuclear fuel element comprising:
 a metallic fuel slug,
 the fuel slug consisting essentially of a uranium (U) and zirconium (Zr) alloy; 
   a protective coating layer of a nitride layer or a carbide layer,
 the protective coating layer is coated on a surface of the fuel slug, which causes the fuel slug to be coated with the single protective coating layer of the nitride layer or the carbide layer,
 the single protective coating layer is formed by nitridation or caburization of the fuel slug, 
 thickness of the single protective coating layer is in a range of 0.5 μm to 100 μm, and 
 the single protective coating layer is preformed on the fuel slug surface prior to fuel slug usage in a fast reactor, 
 the single protective coating layer is configured to prevent interdiffusion between the fuel slug and a cladding tube, to prevent the cladding tube from thinning during fission operation in the fast reactor. 
 
   
     
     
         2 . A fast reactor nuclear fuel element comprising:
 a metallic fuel slug,
 the fuel slug consisting essentially of a uranium (U) and zirconium (Zr) alloy, and one or more selected from the group consisting of plutonium (Pu), thorium (Th),  neptunium  (Np), americium (Am), curium (Cm), lanthanum (La), cerium (Ce), neodymium (Nd), praseodynium (Pr), promethium (Pm), samarium (Sm), europium (Eu), molybdenum (Mo) and gadolinium (Gd); 
   a protective coating layer of an oxide layer, a nitride layer or a carbide layer,
 the protective coating layer is coated on a surface of the fuel slug, which causes the fuel slug to be coated with the single protective coating layer of the oxide layer, the nitride layer or the carbide layer,
 the single protective coating layer is formed by oxidation, nitridation or caburization of the fuel slug, 
 thickness of the single protective coating layer is in a range of 0.5 μm to 100 μm, and 
 the single protective coating layer is preformed on the fuel slug surface prior to fuel slug usage in a fast reactor, 
 the single protective coating layer is configured to prevent interdiffusion between the fuel slug and a cladding tube, to prevent the cladding tube from thinning during fission operation in the fast reactor. 
 
   
     
     
         3 . A nuclear fuel rod configured for use with a fast reactor comprising:
 a fast reactor nuclear fuel element of  claim 1 ; and   a cladding tube sealing the metal fuel slug.   
     
     
         4 . The nuclear fuel rod as set forth in  claim 3 , wherein the cladding tube comprises one or more selected from the group consisting of iron (Fe), chromium (Cr), tungsten (W), molybdenum (Mo), vanadium (V), titanium (i), niobium (Nb), tantalum (Ta), silicon (Si), manganese (Mn), nickel (Ni), carbon (C), nitrogen (N), and boron (B). 
     
     
         5 . A nuclear fuel rod configured for use with a fast reactor comprising:
 a fast reactor nuclear fuel element of  claim 2 ; and   a cladding tube sealing the metal fuel slug.   
     
     
         6 . The nuclear fuel rod as set forth in  claim 5 , wherein the cladding tube comprises one or more selected from the group consisting of iron (Fe), chromium (Cr), tungsten (W), molybdenum (Mo), vanadium (V), titanium (Ti), niobium (Nb), tantalum (Ta), silicon (Si) manganese (Mn), nickel (Ni), carbon (C), nitrogen (N), and boron (B).