�� What you need to know? ��"Understand ferrous metals including: mild steel, high carbon steel, cast and wrought iron their and applications, Understand non ferrous metals including aluminium, copper, zinc, gold, silver and titanium and their applications, Understand the stock forms of both ferrous and non ferrous metals".��
FERROUS AND NON FERROUS METALS
Some metals are pure metals (gold) and others (alloys) are mixtures of different metals. Metals can be classified into two basic groups – ferrous and non-ferrous
1
Ferrous:
2
Non-Ferrous
�� Where do metals come from?��
FERROUS AND NON FERROUS METALS
Most metals are extracted from within in the Earth’s crust combined with other elements in rocks known as ores.
Metals need to be extracted from ores before they can be turned into useful products, such as cars or cutlery.
For example, iron is found combined with oxygen in ores called haematite and magnetite.
�� How are metals made?��
FERROUS AND NON FERROUS METALS
1) HAEMATITE (iron ore), limestone and coke (carbon) are fed in here
2) Hot air is blasted in here
3) The carbon reacts with oxygen from the air to form carbon dioxide.
4) The carbon dioxide reacts with more carbon to form carbon monoxide
6) Molten slag (waste) is tapped off here
5) Carbon monoxide reduces iron oxide to iron. The molten iron is tapped off here
�� What happens when I add carbon to iron?��
FERROUS AND NON FERROUS METALS
Iron is generally soft and ductile when carbon (a very hard, brittle element) is
mixed with iron the characteristics (properties) of iron are greatly improved.
The result is a harder and tougher material.
Increasing the carbon content has the following effects:
• The material becomes harder;
• Toughness reduces;
• Both the medium and high carbon steel can be heat-treated to make them even � stronger and harder.
�� Ferrous Metals �
TYPES OF FERROUS METALS
Metal | Properties | Uses |
Mild Steel | Quite strong and cheap but rusts easily and can’t be hardened or tempered. | Car bodies, screws, nuts, bolts, nails, washing machines. |
High-Carbon Steel | Harder than mild steel and can be hardened and tempered. But it’s not as easy to work and it rusts. | Drills, files, chisels, saws. |
Wrought Iron | Wrought iron is tough, malleable, ductile and easily welded. Has a very low carbon content. | Wrought iron gates, machine beds, The Eiffel Tower. |
Stainless Steel | Hard and won’t rust but is more expensive. | Medical equipment, sinks, kettles, cutlery, e.g. Knifes. |
��Non-Ferrous Metals �
TYPES OF NON FERROUS METALS
Metal | Properties | Uses |
Aluminium | Lightweight and corrosion-resistant but expensive and not as strong as steel. | Aeroplanes, cans, ladders. |
Brass | Quite strong, corrosion –resistant, malleable, ductile and looks good. | Door handles, electrical parts. |
Copper | Relatively soft, malleable and ductile and a very good electrical conductor. | Wiring, pipes. |
Titanium | Low density and is a strong, lustrous, corrosion-resistant with a silver colour. | Used in jet engines, medical and dental implants. |
��STOCK FORMS�You can buy metals in loads of different shapes and sizes.�
TYPES OF METALS
3
Stock Forms
METALS WHERE DO THEY COME FROM PLENERY
� What you need to know? ��"recognise the working characteristics of the common forms of metals; understand the differences between ferrous & non-ferrous metals and how they are used; know that metals can be combined to form alloys"�
What are the three types of metals?
1
Ferrous —contains iron, most are magnetic and will rust.
2
Non Ferrous —does not contain iron, are not magnetic and don’t rust.
3
Alloys— are a mix of metals to improve their properties i.e. Brass.
What are some of the uses of metals?
1
Ferrous —car bodies, screws, nuts & bolts, drills, sinks etc.
2
Non Ferrous —aeroplane bodies, cans, electrical wire etc.
3
Alloys— door handles, taps, electrical parts etc.