Zirconium; symbol Zr is a chemical element with atomic number 40 and atomic weight 91,224 g / mol. It is a bright, whitish gray metal that can be expanded and beaten in solid form at room temperature. In case of low purity, it can be hard and fragile. In addition, zirconium, which is a highly flammable metal in powder form, is less flammable in solid form. It is highly resistant to zirconium acids, salt water and alkalis. Its melting point is 1855 degrees and its boiling point is 4371 degrees. There is always 1/50 of hafnium (Hf) element in zircon. Zirconium has a hexagonal crystalline structure and is very resistant to temperature and corrosion. It can also be found in many different compounds. Approximately 75% of zirconium is made in Australia and South African countries. It is mostly found in Australia territory in the world, but in addition to Australia, it is also located in Brazil, Russia, South Africa and the USA. It is estimated that there are about 60 million tons of zirconium in the world and it is also known to be found in S-type stars. Zirconium fragments were also found in meteor fragments.
Zirconium metal was first discovered in 1789 by Martin Heinrich Klaproth. It was isolated by Jons Jakob Berzelius in 1824. Known minerals are zircon (ZrSiO4) and baddeleyite (ZrO2). The synonyms for Baddeleyit (named after Joseph Baddeley, who discovered it in Sri Lanka in 1892) are zirconium oxide, zirconium dioxide and zirconia. Therefore, zircon and zirconia, which are similar in terms of word structure but different chemical compositions, should not be mixed with each other.
Zirconium metal is used as the building material of nuclear reactors due to its corrosion resistance and high neutron absorption feature. 1% of the zirconium supply goes to the coating of nuclear reactors.
Zirconium metal is used in spacecraft where heat resistance is required. In jet engines and stationary gas turbines, high temperature parts such as burners, blades and blades are preferred because they are more protected by thin ceramic layers, which are usually made of zirconia and yttrium.
Because zirconium has excellent resistance to most corrosion, it is used as an alloying agent in materials exposed to aggressive environments such as surgical instruments, light filaments and watch boxes, as well as in some special applications such as high reactivity of Zirconium with oxygen at high temperatures, explosive primers and receivers in vacuum tubes. Burning zirconium is used as a light source in some photographic flash bulbs.
Zirconium bearing compounds are used in many biomedical applications, including dental implants and crowns, knee and hip prostheses, middle ear ossicular chain reconstruction, and other restorative and prosthetic devices.
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