Properties Of Materials: Glass And Ceramic JSS1 Basic Technology Lesson Note

IDENTIFICATION OF CERAMICS & GLASSES

CONTENT

•             Ceramic materials and properties
•             Glass materials and properties

CERAMIC MATERIALS AND PROPERTIES

Ceramic is a hard brittle heat-resistant material made by firing a mixture of clay and chemicals at high temperatures. Ceramic products are products made from clay and chemical materials.

Examples are clay pots, marbles, tiles, water, water, glass, water basins etc.

PROPERTIES OF CERAMIC MATERIALS

1.         Ceramics are resistant to corrosion.
2.         They can withstand very high temperatures e.g. furnaces and ovens.
3.         They are electrically resistant.
4.         They are usually hard and strong.
5.         They have compressive strength.
6.         They can easily be molded when wet. 
7.         They can easily break when dropped on the ground.

EVALUATION

1.         What is a ceramic?
2.         List five properties of ceramics.

GLASS MATERIALS AND PROPERTIES

Glass is a type of ceramic. Glass is a hard usually transparent material made from sand, lime, potash, soda, and lead oxide. To produce glass, these raw materials are mixed placed in a furnace, and melted. It is then formed into the desired objects.

MAKING GLASS

Making of glass involves the following stages: 

1.         Mixing the raw materials;
2.         Heating (firing) to produce molten glass;
3.         Cooling to form rigid glass;
4.         Heating again and allowing to cool gradually (annealing).

PROPERTIES OF GLASS

1.         It is brittle,
2.         It is transparent and 
3.         Resistant to corrosion.

Examples of glass products are cups, bottles, mirrors, glass tubes, electric bulbs, glass windows, glass doors, eyeglasses, and lenses.

EVALUATION

1.         What are the materials for making glass?
2.         List three properties of glass.