Zirconium has symbol Zr and atomic number 40. It is a metal extracted from the oxide mineral baddeleyite and Zirconium silicate. Zirconium is the nineteenth most abundant element in the earths crust, it is more plentiful than lead and copper. It has an honest tendency to form metallic salts with good electrical conductivity. Due to these properties, it is used in a whole lot of structural components of nuclear reactors.
It was discovered in 1789 by a German chemist Martin Heinrich Klaproth. Its metallic powder was made in 1824 by a Swedish Chemist, Jons J. Berzelius. In 1925, the approach to purify useable amounts of metal was developed by two Dutch chemists J.H. de Boer and Anton E van Arkel. They also invented a thermal iodide procedure to thermally decompose Zirconium tetraiodide.
Fundamental properties of Zirconium Oxide:
Zirconia is a highly refractory material. It offers great chemical and corrosion inertness.
Low thermal conductivity.
Ionic electrical conduction.
Resistance to molten metals.
Use temperatures up to 2400 C.
High fracture toughness.
Zirconium dioxide (ZrO2) commonly known as Zirconia, is a herbal happening metal with a monoclinic crystalline structure. It has same features and design as that of alumina, but gives better finish after surface grinding as compared to alumina. Machining Zirconia is far easier than machining alumina compared to alumina, its threads, big holes Etc. are easily produced. There are three basic principles that should be followed whereas machining Zirconia: high feed rates, slow speeds and a flood coolant system using a water soluble oil lubricant.
Manufacturing of Zirconium Oxide:
Absolutely pure products should be used for the production of high quality ceramics, advanced synthesis methods have been developed for high purity of Zirconia.
Raw material used for manufacturing of Zirconia is the mineral Zircon silicate. ZrO2 can be obtained on an immense scale by melting coke and lime.
Its manufacturing methods include – reactions in the gas phase, molten salt baths, hydrothermal powder synthesis and sol-gel methods.
The Zirconia powder of particle sizes 0.01 to 0.10m can be obtained by gas phase manufacturing. The powder obtained by this approach is further mixed with additives and then green bodies are manufactured by tape casting, dry pressing and slip casting.
After that, the sintering additives remain in the ceramic but the auxiliary substances which are volatile organic compounds are removed from the moulding before the sintering procedure.
The green body is transmuted into a raw product by sintering approach, later polished & grounded as per the software.
The mouldings are endued their actual properties in the sintering procedure. The ceramic powder contracts by reducing to their specific shape. This is obtained by temperature-dependent diffusion procedure.
The speed of solid body diffusion can be increased by appropriate alternative of sintering additives. If solid body diffusion occurs too slowly, sintering should be done with a liquid phase or under specific rigidity.
The sintering procedure done under high temperatures and rigidity increases the production costs of ceramic components.
Typical uses of Zirconium Oxide:
Thread and wire guides.
Hot metal extrusion dies.
Powder compacting dies.
In mill grinding industries.
Used in Oxygen sensors.
Fuel cellular phone membranes.
Precision ball valve and seats.
High temperature induction furnace susceptors.
Rollers and guides for metal tube forming.
Marine pump seals and shaft guides.
Deep well down-hole valve seats.
Machining Zirconia is done through typical methods as being chemically unreactive element requires exceptional high technology tools to produce the best quality products.