Uses of Zirconium and Hafnium

Zirconium and hafnium have very similar chemical properties, invariably occur together in nature, and are difficult to separate. Yet their absorption cross sections for thermal neutrons are very different  

The thermal absorption cross section of zirconium is the lowest of all mechanically strong, high-melting, corrosion-resistant metals. For this reason, zirconium and zirconium-based alloys are the materials preferred for cladding and structural materials in water-cooled, thermal-neutron power reactors. 

When separated from zirconitun, hafniimi abo has valuable nuclear applications. The high cross section, good mechanical strength, and corrosion resistance of hafnium make it an excellent materM for control elements in water-cooled reactors, where it can be used without cladding. 

The amount of hafnium-free zirconium used in nuclear applications is much smaller than the ordinary commercial uses of zirconium metal and compounds, for which costly removal of hafnium is not required. Zirconium metal is used in corrosion-resistant equipment for chemical 

Hafnium metal is used in refractory alloys and in photo flashbulbs where especially high light output is wanted. 

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The uses of zirconium and hafnium compounds based on their thermal and corrosion stability are described in related sections (see below). The most dramatic use of zirconium... 

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