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FAQs

 

1. Is Aluminium ‘Environmentally Friendly’?

Yes. Whilst aluminium requires a significant amount of energy to be produced initially, its high strength-to-weight ratio plays a crucial role in producing lighter vehicles and other forms of transport, and also reduces fuel consumption without compromising performance and safety.
The use of lightweight aluminium components in a vehicle can save six to twelve times the energy taken to produce the primary aluminium used in its construction. For other vehicles, such as trains, ferries and aircraft, the potential savings are even greater.
In the case of building and construction, the use of lightweight materials such as aluminium can significantly reduce environmental impact and provide substantial reductions in energy consumption over the life of the building where it is then 100% recyclable

2. Recycling of Aluminium?

Recycled aluminium generally falls into two broad categories. New scrap resulting from a manufacturing process such as extrusion is often not contaminated and of known quality. This scrap is remelted and reprocessed with very little further treatment. Due to its high value, such scrap enjoys an almost 100% recycle rate.
Old scrap, such as that from beverage cans, building and transport is gathered and recycled via an efficient network of scrap metal merchants which sort and separate it from other metals such as iron and steel. This scrap is most usually remelted by secondary refiners into silicon based alloys used predominantly for aluminium castings.
In Europe, recycling rates of aluminium cans can reach up to 63% whilst rates from buildings and transport are higher again and 85% & 95% respectively.
As recycling of aluminium requires only 5% of the initial energy consumed to create it, recycling one tonne of aluminium saves 5 tonnes of bauxite and 15,000 kilowatt hours of electricity, making excellent environmental and financial sense.

3. How is aluminium created?

Aluminium is created from Bauxite ore. The bauxite is refined to produce alumina. The alumina or aluminium oxide is extracted via a chemical refining process known as the Bayer process resulting in a fine, white powder which is cooled and stored.
The Alumina is smelted to produce aluminium. Widely known as the Hall-Heroult Process, smelting is a complex procedure which initially requires the oxygen content of the alumina to be removed. The alumina is dissolved into a molten solution called cryolite where it is subjected to an electric current of up to 320,000 amps depending on the smelter. The electric current causes a reaction forming aluminium and carbon dioxide. The aluminium in molten form is syphoned out and cast into either pure aluminium or with the addition of other elements such as silicon, copper or magnesium to produce various alloys.

4. In what ways can aluminium be finished?

Depending on the aesthetics, durability or application required, aluminium can be either raw, brushed, polished, powder coated, painted or anodised to achieve a wide range of finishes.

5. What type of aluminium alloys are there?

There are hundreds of commercially available aluminium alloys controlled by an internationally agreed classification system. The choice of alloys provides a vast array of strength, corrosion resistance and workability options.
Generally, alloys fall into two broad categories of either wrought alloys, which are those strengthened by cold work hardening such as rolling and the heat treatable alloys where strength and properties are achieved by heat treatments of various complexity.

6. What are the advantages of aluminium over steel?

In a wide range of applications, aluminium holds many key advantages over steel. Its significantly higher strength to weight ratio allows more efficient use and greater spans, while its extrudeability and machineability offer greater design flexibility. It also offers a wider range of finishing options and is aesthetically pleasing in high visibility applications. In addition it is far more durable in harsh environments, is available in precise tolerances and has a lower life cycle cost.