Ceramics

Ceramics are mostly inorganic crystalline materials characterized by high melting point and low ductility. Such materials are processed via methods other than melting.

Ceramics consist of nonmetallic and metallic elements that are bonded together with ionic and or covalent bonds. They are usually produced via powder compacting and sintering at high temperatures.

General ceramic materials are hard and brittle along with very little ductility and toughness. Their inability to deform plastically is mainly because of directional ionic and or covalent bonds that leave no free electrons. Because of several reasons the ceramics are bad conductors of heat and electricity. Their engineering application makes employ of electrical and thermal insulating properties. The stability of inherent chemical and strong bonding also make ceramic quite able of surviving in hostile environment. High temperature application is individual situation.

Clay, silica as flint and feldspar form the basic ingredients of traditional ceramics. Major constituents of clay are hydrated aluminium silicate as Al₂O₃, SiO₂, H₂O. Minute amounts of other oxides as like: those of Ti, Mg, Fe, Ca, Na and K are present also. Whilst SiO₂ provides stability against high temperature feldspar, as K₂O, Al₂O₃, 6SiO₂ generates glass bond among of refractory components. Traditional ceramics are usually utilized in form of tiles and bricks for construction or like electrical porcelain for electrical insulators. In its latter form this material is highly standardized for large variations and electrical industry are available. Still another class of ceramics called as engineering ceramics typically are made up of pure compounds like aluminium oxide or Al₂O₃, silicon carbide or SiC and silicon nitride or Si₃N₄. These engineering ceramics are utilized for high temperature applications.