Materials Technology - Non-ferrous Metals

Metals

Non-ferrous metals

Non-ferrous metals do not contain any iron. They have different properties to ferrous metals as well as different uses. Non-ferrous metals that are made up of more than one metal are called non-ferrous alloys.

Non-ferrous metals and non-ferrous alloys are not magnetic and they are more resistant to rust.

This group is made up of some of the more common metals such as aluminium, copper, magnesium, silver and lead as well as nickel, tungsten and molybdenum.

Characteristics of non-ferrous metals and alloys.

·         They are more expensive than ferrous metals

·         They are more difficult to find

·         They are very resistant to rust

·         They can conduct heat very well

Name	Colour	Alloy of:	Properties	Uses
Aluminium	Light grey	Not an alloy	Ductile, soft, malleable and very light	Window frames, airplanes and kitchenware
Copper	Reddish brown	Not an alloy	Ductile, can be beaten into shape and conducts heat and electricity	Electrical wiring, tubing, kettles, bowls and pipes
Brass	Yellow	Copper: 65% Zinc: 35% Can be other combination but this is most common	Hard, surface tarnishes and conducts electricity	Parts for electrical fittings and ornaments
Bronze	Light brown	Copper alloy with up to 10% tin, but can also contain Phosphorus, magnesium, aluminium or silicon.	Conducts electricity and resistant to rust	Bearings, electrical connectors, springs and musical instruments, such as bells and saxophones
Lead	Bluish grey	Not an alloy	Soft, heavy, ductile and loses its shape under pressure	Pipes, batteries and roofing

 

Aluminium and aluminium alloys

Properties:         Soft, malleable and ductile

                                Durable and resistant to rust

                                Resistant to attack from chemicals

                                Reflects light very well (cool metal)

Anodised aluminium has a hard aluminium oxide surface layer on it. This layer is made in a special electric process called anodising. It thickens the natural aluminium oxide layer on the service of the aluminium making it even more resistant to rust.

Main uses of aluminium includes:-           containers and packaging such as aluminium tins and tinfoil

Construction materials such as window and door frames, cladding for walls, garden furniture, car bodies and boats.

Mirrors are made by putting a thin layer of aluminium at the back of glass.

Copper and copper alloys:

Copper is easily recognized because it has a reddish-yellow colour. It is one of the world’s most useful metals. It is used as an alloy in brass and bronze and as an alloying element to change the properties of other elements.

Properties:-        Good conductor of heat and electricity

                                Very malleable and ductile

                                Easy to alloy with other metals

                                Very resistant to rust

With almost 400 different types of copper alloys it is used very widely. Ex. Electrical and electronic parts, decorative pots, jewellery, tubes, taps, roof coverings and pipes.

Brass is an alloy of copper that contains up to 45% zinc, and it was one of the first alloys made. If brass contains more than 80% copper it is called gilding metal because of its golden colour. This alloy is often used for decorative objects such as statues and jewellery. Brasses are used in engineering because they are very resistant to rust.

Bronze is an alloy of copper with up to 18% tin and various other elements. Phosphorus bronze is used to make springs. Phosphorus bronze contains can contain even more tin. Up to 20% tin are used in the making of bells.

Lead and lead alloys:

Pure lead is a soft, heavy metal with a low melting point. It is not very strong but very resistant to corrosion. Lead, however is very poisonous to humans. It is often alloyed with antimony and tin to improve its properties. Lead is used for flashing, waterproofing, car batteries and solder.

Titanium and titanium alloys:

Titanium is a silvery-white metal that is expensive to produce. However, it is very light and strong, and is resistant to rust at room temperature and also at much higher temperatures. These properties makes it very suitable for uses such as jet engines, racing cars, golf clubs and the outside of submarines.

Magnesium and magnesium alloys:

Magnesium is one of the lightest materials we can use in engineering. It is also sometimes used as an alloying element in other non-ferrous alloys such as aluminium, lead and zinc. Some of the main uses include ladders, bicycles and sport equipment such as golf clubs. Magnesium is mostly used in alloys with other metals because on its own it is not strong enough.