Key Properties of Aluminium

What is Aluminium?

Aluminium is a metal almost never found in its pure form because it bonds readily with oxygen. It oxidises in the same way that iron rusts, but unlike iron, the resulting oxide sticks to the surface and protects it, making it highly corrosion resistant.

Aluminium is produced by processing bauxite, predominantly mined in Australia. Bauxite a reddish clay like rock primarily composed of aluminium oxide. Aluminium oxide can be put through a version of the Hall-Heroult process to produce a more pure form of aluminium.

Grades of Aluminium

The properties of aluminium can be varied by alloying with other elements to create different grades, making it a very versatile metal. It can be joined using a variety of methods such as soldering, welding, and brazing as well as mechanical methods such as nuts, bolts, rivets, and other fasteners.

Key properties of Aluminium

Corrosion Resistance

Aluminium is very reactive with oxygen, either in air or water and this is the property that makes it corrosion resistant. The reaction with oxygen forms a compact oxide layer on the aluminium surface which acts as a protective layer preventing corrosion in most circumstances. Aluminium will still corrode under certain circumstances, the most common types being atmospheric corrosion, galvanic corrosion, pitting and crevice corrosion.

Corrosion resistance can be enhanced with surface treatments such as anodising, painting or powder coating.

Low density

Low density is one of the most important characteristics of aluminium. The strength to weight ratio of aluminium is high, it is approximately one third of the weight of steel, making it ideal for applications requiring strong but lightweight materials. These include aircraft manufacturing, automotive uses and architecture.

Machinability and formability

Aluminium is flexible and easily formed through various processes including rolling, drawing and extrusion. Generally, aluminium is easy to work into complex shapes from one piece of extruded aluminium without mechanical joinery. Some applications using aluminium components created through this method include heat exchangers, and refrigeration tubing, parts for nuclear facilities and parts for the International Space Station.

Not magnetisable and excellent electrical conductivity

One of the most valuable properties of aluminium is that it is not magnetisable, so it can be used in high voltage applications. It is used in long distance electricity lines, electronics and for shielding electronic devices.

Very reflective of light and heat

Aluminium is a good reflector of both light and heat, this makes it an ideal material for reflectors in light fittings, light shades, insulation, food packaging and rescue blankets.

Impermeable and Odourless

Aluminium, even when rolled very thin, is completely impermeable to light, aroma and taste. It is also non-toxic making it ideal for packaging sensitive products such as pharmaceuticals or food.

Recyclability

Aluminium is 100% recyclable with no loss of qualities, making it a permanent material. The re-melting of aluminium requires only around 5% of the energy required to produce the original material.

All of these qualities vary between the aluminium grades, so it is important to do a bit of research to understand them and enable you to choose the right one for your application.

LASER CUTTING ALUMINIUM

Aluminium is a little more difficult to cut than steel, copper and brass because it is softer and more reflective. It is a bit more prone to burr if the cut settings are not right, but our laser cutting experience coupled with our investment in Trumpf fibre laser machines means that we can provide you with the best quality laser cut aluminium components.

We laser cut aluminium from as thin as 0.5mm up to as thick as 20mm, find out more on our aluminium page. If you would like to place an order, or have any queries, please contact our sales team at sales@lasered.co.uk.