Clean mill aluminium – i.e. how the aluminium looks the moment it comes off the line.

What is aluminium extrusion?

Is it an actual physical thing or is it a process? If you think it’s the latter, then you’re right, aluminium extrusion is, in fact, a process. 

How does aluminium extrusion work?

Aluminium extrusion involves heating aluminium and forcing it through a die to create a shape. The metal is heated in a gas-fired furnace for several minutes until it’s between 400 to 500°.

While it may be incredibly hot, believe it or not, it’s not hot enough to turn into liquid form. Once it has reached 400 to 500°, the aluminium is still malleable; not too dissimilar to the consistency of toothpaste. Once extruded, it’s then forced through a die and air or water-cooled.

Aluminium extrusion is a fantastic process. It takes around six hours to heat, extrude, age and pack. There are multiple finishes once aluminium is extruded. Such as:

Clean mill – i.e. how the aluminium looks the moment it comes off the line.

Clean mill aluminium

Anodised – i.e. when the aluminium has been submerged in an acid electrolyte bath and passed through an electric current to create a matte or bright silver finish.

Annodised aluminium

Powder-coated – i.e. the aluminium is covered with a fine powder coating that’s made from either polyester or epoxy resin and has a chalk-like appearance.

Powder coated aluminium

In addition to being able to produce aluminium extrusion in various finishes, it’s also possible to design in specific features. For instance:

  • Screw ports and hinge mechanisms
  • Patterned surfaces
  • Heat sinks
  • Snap fits

Cross section image

We process 26,000 tonnes of aluminium a year

And around 12,000 tonnes of that is aluminium extrusion. We’ve worked hard over the years to perfect all of our processes, aluminium extrusion included.

Over the last 15 years specifically, we’ve implemented some of the latest game-changing technologies, which includes industry-leading x-ray technology.

We’re continuously striving to push the boundaries, and if find we could be working more efficiently or effectively in certain areas, we make the necessary improvements to make it happen. Equipment investment is pivotal to our pioneering results and ultimately helping our customers reduce their carbon emissions.

Our work, and the results we’ve seen as a company and achieved for our customers so far, is just the starting point. For every tonne of extrusion we recycle, we’re preventing around three tonnes of carbon from being released into the atmosphere. Our mission is to help further drive down carbon emissions sector-wide – watch this space, the best is yet to come.

For more on the benefits of aluminium recycling, read this blog, ‘What are the advantages of recycling aluminium?’

To discuss your aluminium recycling requirements with us, email our Commercial Manager, Ed George, at ed.george@alutrade.co.uk