Ceramic: An inorganic non-metallic solid
A ceramic is an inorganic non-metallic solid formed with metal and non-metal materials. Its surface is made hard by heating it on high temperature and to provide it high resistivity, hard and brittle surface.
Types of ceramics
There are two types of ceramics material which is discussed below:
- Traditional Ceramics: The traditional ceramic materials are made by clay materials and quartz sand. Ball clay, China clay, Feldspar, Silica, Dolomite, Talc, Calcite and Nepheline are the common materials used for the formation of ceramic. The materials used have dry strength, plasticity, shrinkage. Hence by mixing in different forms are acquired for the final output. Powder preparation is most significant step in the ceramic formation. Surface area, particle size and distribution, particle shape, density, etc. are the common factors which are considered at the time of production. Powder should have definite particle size, particle shape, and particle density. Milling is done to get the desired particle size. Pottery, tableware, sanitary ware, tiles, structural clay products, refractory’s, blocks, and electrical porcelain are some of the products of traditional ceramics.
- Advanced Ceramics: Industrial use of ceramic in electrical, electronics, optical and magnetic applications has changed its shape from powder to thick material with varied densities. The highly advance production techniques are used so that the produced ceramic powders possess sufficient purity and can acquire a definite shape. The chemical reactions with the ceramic powder such as Sol-gel processing and liquid-gas reactions are processed to produce Si3N4. Many of these methods are very costly. Therefore, powder preparation is always a cost factor in the advanced ceramics industry.
Preparation of Ceramic
Other than firing which is the traditional way of forming ceramic, many other new techniques are used. The techniques of preparing ceramic are given below:
- Extrusion: With the help of a shaped tool, the ceramic powder is converted into paste like material to form a flexible shape.
- Jiggering: it is the process of converting ceramic powder into rotating mould form so that it can be used in electronic and electrical applications.
- Hot pressing: It is the process of heating the powder at high temperature and then converting into a sheet format which can be used further in different applications.
- Reaction Bonding: A new advanced form of making ceramic which involves forming of silicon powder into a desired shape and then heating it with nitrogen gas. A flexible shape is acquired with high density which can be used in industrial applications.
Applications of Ceramic
- In electronic and electrical industries advanced ceramic materials like Barium Titanate (BaTiO3), piezoelectric materials and semiconductor materials are heavily used for producing ceramic capacitors, vibratos, temperature sensors, oscillators, etc. The ceramics used are called functional ceramics.
- The property of ferro electricity like in Lead zirconate titanate, lead titanate, barium titanate is used to produce applications like sensors, pumps, sonar, microphones, etc.
- Magnetic ceramics are another type of advanced ceramic material that is used for the production of antennas and inductors.
- Bio ceramics like Alumina with high density and purity is used to dental implants.
- Eye glasses, chemical ware, and the replacement of hips and knees, etc. are medical applications of bio ceramic materials.
- Traditional ceramics have been used for civilizations; advanced ceramics is a recently developed field.
- Ceramic is used as a catalytic convertor which is used for controlling air pollution.
- Ceramic is preferred as a light weight components and preferred over metal in many industrial components.
- The piezoelectric ceramic materials can produce small current when used under stress and strain; it can be used to detect metal failures or even the natural calamities like earth quake.
- It can be used as coating in the fluorescent bulbs and tubes.