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ZIRCONIUM - A NUCLEAR METAL AND ITS MANUFACTURING PROPERTIES

Zirconium minerals contain 0.5 to 2 percent hafnium which is a strong absorber of neutrons and must therefore be removed. The main use of zirconium is for cladding fuel elements and for structural components in water-cooled systems. So it must have increased corrosion resistance. Zircaloy-2 containing 1.5% Zn , 0.1 % Fe , 0.05 % Ni and 0.1 % Cr provides better corrosion resistance and is generally used in water-cooled reactors. Zirconium has a relatively poor resistance to Co2 at elevated temperatures, but this is improved by the addition of 0.5 % Cu , 0.5% Mo with an increase of tensile strength to 51 kg-f / mm2. (510 M pa) and improved creep resistance at 450*C. This zirconium is especially useful in gas cooled reactors. The melting point of Zirconium is 1750*C.






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