What is Aluminium Extrusion?

Aluminium extrusion is the technique used to transform aluminium alloy into objects with a definitive cross-sectional profile for a wide range of uses. The extrusion process makes the most of aluminium’s unique combination of physical characteristics. Its malleability allows it to be easily extruded and machined, and yet at one third the density and stiffness of steel the resulting products offer exceptional strength and stability.

The Process of Aluminium Extrusion:

  • After designing and creating the shape of your extrusion a die is cut, made from tool steel
  • The aluminium in the form of a billet is heated in a furnace to around 450°C– 500°C
  • The heated billet is then transferred and loaded into the extrusion press
  • The billet is then forced through the die under great pressure, and the profile is squeezed out like toothpaste from a tube
  • When the extruded profile exits the die it passes onto a table where it is cooled with water or air
  • To then straighten and relieve the extrusion of any stresses within the aluminium it is passed to a stretcher
  • The extruded profile is then cut into suitable lengths and artificially aged to achieve its strength
  • Age hardening takes place in ovens at about 190°C for between 4 to 8hrs
  • The aluminium extrusion is then ready to be packed and shipped to the customer for use

Additional complexities may be applied during this process to further customize the extruded parts. For example, to create hollow sections, pins or piercing mandrels are placed inside the die. After the extrusion process a variety of options are available to adjust the colour, texture and brightness of the aluminium finish. This may include aluminium anodizing or painting.