The primary difference between ceramics and other materials is the chemical bonds that hold these materials together.
Ceramics are formed by what type of bond.
These chemical bonds are of two types.
Although they can contain covalent bonds such as the si o si linkages in glass they are often characterized by ionic bonds between positive and negative ions.
Graphene is currently considered the strongest known material.
Two types of bonds are found in ceramics.
This electron transfer creates positive metal ions cations and negative nonmetal ions anions which are attracted to each other through coulombic attraction.
The atoms in ceramic materials are held together by a chemical bond.
A common definition of a ceramic is a hard material that is held together with ionic and covalent bonds.
Underlying many of the properties found in ceramics are the strong primary bonds that hold the atoms together and form the ceramic material.
The bonding of atoms together is much stronger in covalent and ionic bonding than in metallic.
The two most common chemical bonds for ceramic materials are covalent and ionic.
In each molecule the bonds between the atoms are strong but the bonds between molecules are usually weak.
Compounds with covalent bonds may be solid liquid or gas at room temperature depending on the number of atoms in the compound.
Electronegativity is the capability of the nucleus in an atom to attract and retain all the electrons within the atom itself and depends on the number of electrons and the distance of the electrons in the outer shells from the nucleus.
The ionic bond occurs between a metal and a nonmetal in other words two elements with very different electronegativity.
A material held together by either type of bond will tend to fracture before any plastic deformation takes place which results in poor toughness in these materials.
Recall that the predominant bonding for ceramic materials is ionic bonding.
They are either ionic in character involving a transfer of bonding electrons from electropositive atoms to electronegative atoms or they are covalent in character involving orbital sharing of electrons between the constituent atoms or ions.
Many ceramic materials have covalent bonds.
This makes many solid materials with covalent bonds brittle.
The high energy of covalent bonds makes these ceramics very stable with regard to chemical and thermal changes.
In ionic bonding a metal atom donates electrons and a nonmetal atom accepts electrons.
The atoms in these ceramics are arranged so that each pair of nearest neighbour atoms forms a chemical bond by sharing a pair of electrons.
Noncrystalline the more translucent it will appear and the more crystalline the more opaque.
For metals the chemical bond is called the metallic bond.
These bonds are defined by a cloud of shared electrons with the ability to move easily when energy is applied.
Additionally carbon based materials such as carbon fiber carbon nanotubes and graphene can be considered ceramics.
Ceramics can vary in opacity from very translucent to very opaque.
Ceramic materials are usually ionic or covalent bonded materials and can be crystalline or amorphous.
