Zirconium alloys for a nuclear fuel cladding having a superior oxidation resistance in a severe reactor operation condition and methods of preparing a zirconium alloy nuclear cladding by using thereof

A method of preparing a zirconium alloy nuclear fuel cladding comprising:

• manufacturing an ingot by vacuum arc remelting and then cooling the zirconium alloy comprising 1.8 to 2.0 wt % of niobium (Nb);
• at least one element selected from the group consisting of iron (Fe), chromium (Cr) and copper (Cu);
• 0.1 to 0.15 wt % of oxygen (O), 0.008 to 0.012 wt % of silicon (Si) and a remaining amount of zirconium (Zr),
• in which, an amount of the iron (Fe) being 0.1 to 0.4 wt %, an amount of the chromium (Cr) being 0.05 to 0.2 wt %, and an amount of the copper (Cu) being 0.03 to 0.2 wt %;
• forging thus manufactured ingot in Step 1 (Step 2);
• solution heat treating and cooling the forged ingot in Step 2 (Step 3);
• hot processing by extruding the cooled ingot in Step 3 (Step 4);
• initially heat treating the extruded shell in Step 4 (Step 5);
• cold processing the heat treated and extruded shell in Step 5, the zirconium alloy nuclear fuel cladding being prepared by conducting intermediate heat treating in the middle of the cold processing (Step 6);
• and
• finally heat treating the thus prepared zirconium alloy nuclear fuel cladding to prepare a nuclear fuel cladding (Step 7).