Martensitic oxide dispersion strengthened alloy with enhanced high-temperature strength and creep property, and method of manufacturing the same

Abstract

The present application discloses a martensitic oxide dispersion-strengthened alloy having enhanced high-temperature strength and creep properties. The alloy includes chromium (Cr) of 8 to 12% by weight, yttria (Y 2 O 3 ) of 0.1 to 0.5% by weight, carbon (C) of 0.02 to 0.2% by weight, molybdenum (Mo) of 0.2 to 2% by weight, titanium (Ti) of 0.01 to 0.3% by weight, zirconium (Zr) of 0.01 to 0.2% by weight, nickel (Ni) of 0.05 to 0.2% by weight and the balance of iron (Fe). The application also discloses a method of making the alloy.

What is claimed is: 
     
         1 . A martensitic oxide dispersion-strengthened alloy comprising:
 chromium (Cr) of 8 to 12% by weight,   yttria (Y 2 O 3 ) of 0.1 to 0.5% by weight,   carbon (C) of 0.02 to 0.2% by weight,   molybdenum (Mo) of 0.2 to 2% by weight,   titanium (Ti) of 0.01 to 0.3% by weight,   zirconium (Zr) of 0.01 to 0.2% by weight,   nickel (Ni) of 0.05 to 0.2% by weight, and   the balance of iron (Fe).   
     
     
         2 . The martensitic oxide dispersion-strengthened alloy of  claim 1 , wherein the sum of titanium (Ti), zirconium (Zr) and nickel (Ni) in the alloy is 0.5% by weight or less with reference to the total weight of the alloy. 
     
     
         3 . The martensitic oxide dispersion-strengthened alloy of  claim 1 , wherein the martensitic oxide dispersion-strengthened alloy is shaped to form at least one of a a nuclear fuel cladding, a wire, an end plug and a duct of a fast reactor. 
     
     
         4 . A method of manufacturing a martensitic oxide dispersion-strengthened alloy having high-temperature strength and creep properties, the method comprising:
 mixing yttria (Y 2 O 3 ) powder with powder of carbon (C), iron (Fe), chromium (Cr), molybdenum (Mo), titanium (Ti), zirconium (Zr) and nickel (Ni) to provide alloy powder;   charging alloy powder in a container and degassing the alloy powder;   hot-working the degassed alloy powder to produce an oxide dispersion-strengthened alloy; and   cold-working the hot-wrought oxide dispersion-strengthened alloy.   
     
     
         5 . The method of  claim 4 , wherein the alloy powder comprises:
 chromium (Cr) of 8 to 12% by weight,   yttria (Y 2 O 3 ) of 0.1 to 0.5% by weight,   carbon (C) of 0.02 to 0.2% by weight,   molybdenum (Mo) of 0.2 to 2% by weight,   titanium (Ti) of 0.01 to 0.3% by weight,   zirconium (Zr) of 0.01 to 0.2% by weight,   nickel (Ni) of 0.05 to 0.2% by weight and   the balance of iron (Fe),   wherein the sum of titanium (Ti), zirconium (Zr) and nickel (Ni) in the alloy powder is 0.5% by weight or less with reference to the total weight of the alloy powder.   
     
     
         6 . The method of  claim 4 , wherein the hot working is performed using at least one process selected from the group consisting of a hot isostatic pressing process, a hot forging process, a hot rolling process, a hot extrusion process, and a combination thereof. 
     
     
         7 . The method of  claim 4 , wherein the cold working is performed using at least one process selected from the group consisting of a cold rolling process, a cold drawing process, a cold pilgering process, and a combination thereof.