Abstract: Disclosed are a zirconium alloy for a nuclear fuel cladding having a good oxidation resistance in a severe reactor operation condition and a method of preparing zirconium alloy nuclear fuel claddings by using thereof. The zirconium alloy includes 1.8 to 2.0 wt % of niobium (Nb); at least one element selected from 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). The amount of Fe is 0.1 to 0.4 wt %, the amount of Cr is 0.05 to 0.2 wt %, and the amount of Cu is 0.03 to 0.2 wt %. A good oxidation resistance of the nuclear fuel cladding may be confirmed under a severe reactor operation condition at an accident condition as well as a normal operating condition of a reactor, thereby improving economic efficiency and safety.

Abstract: A syntactic metal foam composite that is substantially fully dense except for syntactic porosity is formed from a mixture of ceramic microballoons and matrix forming metal. The ceramic microballoons have a uniaxial crush strength and a much higher omniaxial crush strength. The mixture is continuously constrained while it is consolidated. The constraining force is less than the omniaxial crush strength. The substantially fully dense syntactic metal foam composite is then constrained and deformation worked at a substantially constant volume. The deformation working is typically performed at a yield strength that is adjusted by way of selecting a working temperature at which the yield strength is approximately less than the omniaxial crush strength of the included ceramic microballoons. This deformation causes at least work hardening and grain refinement in the matrix metal.