Structure Of Metal And Ceramics

Ceramics are by definition natural or synthetic inorganic non metallic polycrystalline materials.

Structure of metal and ceramics.

In atomic structure they are most often crystalline although they also may contain a combination of glassy and crystalline phases. Most ceramics usually contain both metallic and nonmetallic elements with ionic or covalent bonds. The bonding of atoms together is much stronger in covalent and ionic bonding than in metallic. Bonding ranges from ionic to covalent.

Usually they are metal oxides that is compounds of metallic elements and oxygen but many ceramics especially advanced ceramics are compounds of metallic elements and carbon nitrogen or sulfur. Polycrystalline materials are formed by multiple crystal grains joined together during the production process whereas monocrystalline materials are grown as one three dimensional crystal. The properties of ceramics however also depend on their microstructure. The metal is used as a binder for an oxide boride or carbide.

A cermet is a composite material composed of ceramic and metal materials. Charge balances and relative ion size plays key roles in determining structure and properties. The atoms in ceramic materials are held together by a chemical bond. For metals the chemical bond is called the metallic bond.

Depending on the physical structure of the material cermets can also be metal matrix. Therefore the structure the metallic atoms the structure of the nonmetallic atoms and the balance of charges produced by the valence electrons must be considered. Sometimes even monocrystalline materials such as diamond and sapphire are erroneously included under the term ceramics. The two most common chemical bonds for ceramic materials are covalent and ionic.