All metals fall into 3 basic categories ~ Ferrous, Non-ferrous and Alloys.

Ferrous metals are composed primarily of Iron (chemical symbol Fe, hence ferrous), non-ferrous metals are not.
An alloy is a metal compound produced when a metal is combined with one or more other elements.

Ferrous Metals

For the purposes of this course you only need to be aware of Cast Iron.
Cast Iron is the material which sparked off the industrial revolution in the 18th century. The large scale production of this strong, rigid, and cheap material fuelled the designs and schemes of engineers, which in turn led to the industrialisation of the western world.
Cast Iron is a poor conductor of heat, has a high tensile strength and is relatively brittle. Manhole covers, engine blocks are examples of everyday items which have been cast in Iron

Non-ferrous Metals

The following is a list of "pure", non-ferrous metals. In fact most of them are useless in their pure form and will often contain traces of other elements to improve their characteristics. The point at which they become classified alloys is a bit hazy but they are not regarded as alloys.

Aluminium ~ Malleable, ductile, low density, corrosion resistant.
Copper ~ Soft, malleable, ductile, high melting point, excellent thermal and electrical conductor.
Lead ~ Very soft, malleable, very dense, very low melting point, toxic.
Tin ~ Low density, soft, malleable, corrosion resistant.
Zinc ~ Corrosion resistant, often used as a protective coating for steel.
Ferrous Alloys

There is only one ferrous alloy that you need to concern yourself with and that is Steel. It is obtained by alloying Iron with Carbon although the quantities of Carbon involved are small.

Low-Carbon Steel < 0.3% Carbon
Medium-Carbon Steel 0.3-0.6% Carbon
High-Carbon Steel 0.6-1.7% Carbon

90% of the steel produced is Low-Carbon or Mild Steel. The lower the Carbon content, the greater the ductility. A higher Carbon content will increase the strength at the cost of ductility.
Mild Steel is either hot-rolled into crude sections to form Black Mild Steel, or can be drawn through a die to produce steel with a bright surface appearance and more accurate cross section, called Bright Drawn Mild Steel.
High Carbon Steel is also referred to as Tool Steel (for obvious reasons) whilst Carbon Steels combined with the following elements produce the following steels.

Carbon Steel + 18% Tungsten ~ High Speed Steel (Lathe, milling cutters)
Carbon Steel + 12% Chromium~ Stainless Steel (Sinks,cutlery)

Non-ferrous Alloys

The purpose of an alloy is to change one or more of the properties of a material. This is particularly the case for Aluminium which in its pure state does not have the strength-to-weight ratio required for aircraft construction.

There are 2 non-ferrous metals which are commonly alloyed. Copper and Aluminium.

Copper 60% + Zinc 40% ~ Brass, which has greatly improved strength characteristics over Copper but with no great reduction in conductivity.
Easily machined and a good bearing surfaces.
Copper 80% + Tin 20% ~ Bronze, which is used in castings for statues and in marine applications.

Aluminium 96% + Copper 4% ~ Duralumin, a higher tensile strength and improved strength to weight ratio version of Aluminium.

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