Definition of Ceramics :

The word ceramics is of Greek origin ( keromos ) meaning potter’s earth or day ceramics. In present days, Ceramic is used to deflate wide range of silicates, metallic oxides and other combinations. Clay products are the most Common and appropriate example of ceramic materials.

General Properties of Ceramics :

• Ceramics are hard and brittle and amorphous (non-crystalline) or glossy.
• These are bonded by ionic and covale nt bonds, as a result at this bond there are no free electrons in their structure, which makes them thermal and electrical insulators.
• At low temperature they deform elastically. Whereas the same material may undergo viscous flow at some other stress conditions.

Classification of Ceramics :

Based on the internal structure, ceramics can be classified into three types.

Clay Products :

Clay with right amount of water possess high degree of plasticity. These clays can be moulded into any shape. These moulds when dried and burned possess good strength. The major forms in which clay products are used as building materials are :

• Tiles.
• Bricks.
• Porcelain.
• Terra-cotta.
• Earthen wares.
• Stone wares

Refractories :

A refractory material is one that can retain its strength at high temperature. They can be used as linings for furnaces, kilns, incinerators and reactors. The oxides of aluminium, silicon and magnesium are the most important materials used in the manufacturing of refractories.

Glass :

It is not simple compound but a combination of several compounds. It is a mixture of a number of metallic silicates.  It is amorphous, transparent or translucent. It can also be defined as a solidified super cooled solution of various metallic silicates having infinite viscosity.

• Manufacture of Glass :

Manufacturing process of glass essentially consists of following five steps.

1. Collection of raw material.
2. Batch Preparation.
3. Melting.
4. Fabrication.
5. Annealing.