How Does Aluminum Extrusion Work?

The aluminum extrusion process can be carried out in one of two ways: hot extrusion or cold extrusion. There are reasons to use both methods. Hot extrusion allows for greater volumes of aluminum to be fed into the die, quickly and at lower pressure, while cold extrusion can produce mechanically superior parts with a good surface finish and resistance to oxidization.

hot extrusion process
To extrude aluminum via the hot extrusion process, aluminum billets must first be cut to an appropriate size. They are then heated in an oven to a temperature between 300 °C and 600 °C, making the metal supple but not liquid.
When the cut aluminum billets are heated, a ram powered by hydraulic pressure forces them into the die, which may have a standard aperture (i.e. a round or square hole) or a custom-made profile. A huge amount of pressure — around 10,000,000 pounds — is required to force the heated aluminum through the die.
The extrusions are then cooled on a cooling table, before being cut into lengths according to the customer’s demands. Heat treatment can also be applied to harden the aluminum.



Common Extrusion Applications
AerospaceAutomotiveTrainsShipsConstruction IndustryMedical DevicesDisplay IndustryHeatsinkElectronicsAutomation

Standard Aluminum Extrusion Profiles
Custom aluminum extrusion profiles can be cut to any 2D cross-sectional shape. However, there are several standard aluminum extrusion profiles suitable for many projects, including extruded aluminum bar and extruded aluminum channel of various forms.
Standard profiles include:
Circular bar Square bar Circular tube Square tube L-shape U-shape T-shape C-shape J-shape F-shape
Profiles also come in standard sizes and series. These include:
2020 aluminum extrusion (20 mm x 20 mm) 80/20 aluminum extrusion (T-slot aluminum extrusion) 2040 aluminum extrusion (20 mm x 40 mm) 3030 aluminum extrusion (30 mm x 30 mm)

Custom Aluminum Extrusion Profiles

Standard aluminum extrusion profiles (like extruded aluminum channel or extruded aluminum bar) are typically mass manufactured by extrusion specialists; if you need large quantities of standard extruded aluminum profiles, you are better off using the services of one of these companies.
However, for custom aluminum extrusion profiles with a nonstandard aluminum extruded shape, XTJ may be a better option. That’s because we accept low-volume extrusion orders — for prototyping and small batch production — allowing you to experiment with custom profiles.
In addition to creating custom aluminum extrusion profiles using custom dies, we can combine extrusion with other manufacturing processes (like CNC machining) to produce custom final parts. This can allow us to make parts faster and more affordably, especially if the majority of the part has a consistent cross-section.
Example operations:

Creating a custom extrusion, then using a CNC mill to add details, holes, or threads.

Creating a round extrusion, then using a CNC lathe to add taper or other features.

Creating a custom extrusion, then adding text or other engraving with a laser cutter.



Finishing Options for Aluminum Extrusions

Aluminum extrusion is used to mass produce lots of non-cosmetic parts like tubing and frames, where finishing may not be especially important. However, custom aluminum extrusion is also used to produce high-value products which may benefits from the addition of color, text, logos, and other finishing procedures.
Suitable surface finishing procedures for aluminum extrusion include:
Finishing Options for Aluminum Extrusions

Basic mechanical finishing: Treatments like buffing, bead blasting, and grinding can be carried out to adjust the surface quality of aluminum extrusions, sometimes in preparation for other surface finishes.
Anodization: Aluminum extrusions can be anodized to give them a scratch-resistant and oxidization-resistant coating with an excellent cosmetic appearance.
Painting: Whether the part needs a matte, gloss, or textured finish, painting is an effective way to alter the color and surface appearance of an aluminum extrusion.
Powder coating: Powder coating is a suitable alternative to anodizing, giving excellent chemical resistance and consistency of tone.
Silk-screen printing: One of the simplest ways to add text and logos to aluminum extrusions, silk-screen printing is cheaper than machine-based finishing procedures.
Laser engraving: Laser engraving can be used to add detail, including text, to an extrusion, and it will not rub off over time. It is therefore useful for essential features like part serial numbers.


Applications of Aluminum Extrusion

Aluminum extrusions are used in heavy industry, aerospace, the food industry, and elsewhere. Common aluminum extrusions include extruded aluminum heatsinks and profiles for tracks, frames, and rails.

Industrial: Extruded aluminum can be used to make industrial equipment like workbenches and carts, as well as extruded aluminum frames / extruded aluminum framing. Standard framing systems include extruded aluminum T-slot structural framing (80/20 extruded aluminum framing).
Construction: Architecture and construction provide several uses for aluminum extrusion such as extruded aluminum rails, balustrades, and ladders.
Electrical: Aluminum is electrically conductive and is therefore useful in its extruded form for lighting components such as LED aluminum extrusions, solar panel support structures, and more.
Transport: Extruded aluminum is good for fabricating items like automotive, horse, and boat trailers.
Applications of Aluminum Extrusion


Aluminum & Plastic Extrusion FAQ

Why should I use XTJ over a dedicated extrusion company?
We specialize in low-volume manufacturing. If you require a small to medium-size order, other companies may not accommodate your needs.
Can I specify an aluminum alloy?
Our most commonly used alloys are 6061 and 6063, which contain high levels of magnesium and silicone. Both are highly corrosion resistant.
You may specify a different aluminum alloy, and we will review the feasibility when providing you with a quotation.
Who manufactures the extrusions?
We have a selection of trusted extrusion partners who fulfill our orders, but XTJ will do post-machining and check the parts before shipment.


XTJ is a leading OEM Manufacturer that is dedicated to providing one-stop manufacturing solutions from prototype to production. We are proud to be an ISO 9001 certified system quality management company and we are determined to create value in every customer relationship. We do that through collaboration, innovation, process improvements, and exceptional workmanship.




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