8.3.1 Ceramics
Ceramics
- Ceramic is a substance that is made from clay and hardened by heat in a furnace maintained at a high temperature.
- Clay is composed of aluminosilicate with sand and iron(III) oxide as impurities.
- Examples of ceramics include
- Tiles
- Cement
- Bricks
- porcelain
- The properties of ceramics include the following:
- The differences between the properties of ceramics, metals and non-metals are given below
| Property | Metals | Non-metals | Ceramic |
| Hardness | Hard but malleable and ductile | Soft and brittle | Hard but brittle |
| Density | High | Low | Average |
| Melting point | High | Low | Very high |
| Resistance to heat | High | Low | Very high |
| Heat and Electrical conductivity | Good conductor | Good insulator | Good insulator |
| Chemical reactions | Corrodes | Corrodes | Stable, does not corrode |
New Uses of Ceramics
Car Engine Block
- When clay is heated with magnesium oxide, the ceramic that is produced has a high resistance to heat.
- This material is used to build the engine blocks in cars as they can withstand high temperatures.
Superconductors
- Superconductors are electrical conductors which have almost zero (0) electrical resistance. Therefore, this conductor minimises the loss of electrical energy through heat.
- Yttrium barium copper oxide is a type of ceramic superconductor
- Superconductors are used to make magnets which are light but thousands of times stronger than the normal magnet.
Comparing Glass and Ceramic
Common Properties of Glass and Ceramics
- Hard
- Strong but brittle
- Chemically inactive
- Poor conductor of heat and electricity
- High melting point – heat resistant
- Cannot be compressed easily