Ceramics

 

What are ceramics?

Ceramics are hard and strong materials. They are made by heating a soft material in a very hot oven called a kiln. The kiln can change its temperature for different kinds of clay and can go up to more than 1300 °C.

The soft materials can be shaped before they are heated. Clay is one example of a soft material.

When the soft materials are heated, they become harder materials that we call ceramics.

Clay is shaped on a potter’s wheel.

 

The firing process has three stages:

 

• The clay loses water as it gets hotter.
• The material changes its composition because of chemical reactions.
• Some of the substances in the clay melt and become hard when the ceramic cools down.

 

Clay is heated to very high temperatures in a kiln.

 

Properties of ceramics

Common properties of ceramics include:

 

• Hardness.
• Strength under compression.
• Brittleness (ceramics can shatter when struck).
• Resistance to heat.

 

Uses of ceramics:

Ceramics have a wide range of uses including:

 

• Structural: Ceramics are strong materials that can be used for building products. For example, bricks are made by heating shaped clay in a kiln.
• Household items: Ceramics can have any shape and a smooth (porous) surface that does not let liquids in. This makes them hygienic and prevents germs from spreading. For example, ceramics are used for making dishes, toilets, and tiles.
• Technical: Ceramics are light and heat-resistant materials that are useful for engineering. For example, a ceramic structure with many holes supports the metals that make the chemical reactions faster in catalytic converters, which are in car exhaust systems.
• Decorative: Terracotta is a type of ceramic that is used for decoration. It is heated at lower temperatures and not glazed, so the colour of the clay shows. It is often used for making sculptures.

 

The Terracotta Army Source: kevinmcgill from Den Bosch, Netherlands - KAM_5111

 

Summary:

 

• Ceramics are made from soft materials that become hard and brittle when they are heated.
• Ceramics have many properties that make them useful for different purposes.
• Some of the uses of ceramics are easy to see, like cups for coffee, but some are hidden, like parts of car engines.