Zirconium, Hafnium, and Vanadium
These three elements are often the ‘pinch of seasoning’ that, when added to molten metal, give alloys outstanding performance. Each in its own way provides unique properties to the final metal.
Zirconium scrap, as pure and alloy, is often found as trim and turnings from the production of nuclear reactor components and chemical process equipment. Used Zirconium sputter targets can be found as scrap from various applications, typically optical and hardness coatings. There are many different Zirconium alloys produced, most of which can be recycled.
When Zirconium scrap is received, Exotech must clean and size the metal to meet the specifications as an alloy additive. Care is taken to observe the flammable nature of Zirconium, particularly when processing Zirconium machine turnings.
Hafnium scrap is not a common scrap metal. When found, however, it commands a high value. Hafnium is produced as a byproduct of making high purity Zirconium, where Hafnium is present as only 2% of Zirconium in Zirconium minerals.
While chemically similar to Zirconium, particularly in its corrosion resistance, Hafnium performs in exactly the opposite mode of Zirconium in nuclear applications. Where Zirconium is transparent to neutrons, Hafnium is an excellent absorber of neutrons. Because of this property of Hafnium, it is used extensively as a control rod in nuclear applications. Thus the two elements must be separated for use in the nuclear industry.
Hafnium is widely used as an alloy additive in high performance Nickel alloys. Its value and application is dependent on the Zirconium content.
Hafnium scrap is generated from the manufacture of electronic devices in the form of used sputter targets and evaporation sources, principally in the manufacture of microprocessors. It is generated as scrap from making certain gas filled and incandescent lamps, plasma cutting electrodes, certain aerospace applications because of its corrosion resistance. Production scrap from the manufacture of nuclear control rods is another source. Used control rods cannot be used as a source of Hafnium scrap because of residual radioactivity.
About 85% of the Vanadium produced is used as a steel additive. Vanadium-steel alloys are very tough and are used for armor plate, axles, tools, piston rods and crankshafts. Another 10% goes into Titanium alloys where it enhances Titanium’s mechanical properties. The remaining 5% goes into all other applications such as high temperature Nickel alloys.
While pure Vanadium scrap is hard to find, it is highly desired and valuable. Certain high content Vanadium alloys are also prized as a source of Vanadium in specialty alloys.