Which Aluminium Alloy Should I Choose for my CNC Machined Parts?

Aluminium alloys can be machined rapidly and economically. Because of their complex metallurgical structure, their machining characteristics are superior to those of pure aluminium. Nevertheless, some alloys are more common than others when it comes to their use in CNC machined parts. This article highlights a few of the most common ones.

EN AW-2007 (AlCu4PbMgMn)

This copper alloy, which typically contains between 4.0 and 5.0 % copper, is quite suitable for producing machine parts, bolts and rivets. It looks very much like EN AW-2011, but it is yet a bit harder. It is a short-chipped alloy, which is suitable for treatment, threads and high machining speeds. This alloy has a low corrosion resistance though and is not suitable for welding because of the high content of copper. It is also not approved by the ROHS.

EN AW-5083 (Al Mg4.5Mn0.7)

5083 aluminium is known for its exceptional performance in extreme environments. It contains magnesium and small traces of chromium and manganese. This alloy is highly resistant to attack by both seawater and industrial chemical environments and also retains exceptional strength after welding. It has the highest strength of the non-heat treatable alloys. Since this alloy is capable of withstanding extremely low temperatures without brittleness or loss of properties, it is especially suited to the cryogenic market.

EN AW 6082 (Al SilMgMn)

In plate form, 6082 aluminium is one of the most commonly used alloy for general machining. It is widely used in Europe and has replaced 6061 alloy in many applications, primarily due to its higher strength (from a large amount of manganese) and its excellent resistance to corrosion. It is typically seen in transport, scaffolding, bridges and general engineering. It has good finishing characteristics and responds well to the most common anodic coatings (i.e., clear, clear and dye, hardcoat).

EN AW 7075 (Al Zn5.5MgCu)

With zinc as its primary alloying element, this member of the 7000 series alloys is exceptionally strong. It is one of the strongest alloys available and its strength is comparable to many types of steel. Although it has high strength, it has lower corrosion resistance than other common aluminum alloys and does not offer the same levels of machinability or weldability. Due to its high strength, it is often used in applications where it will come under high stress such as aircraft wing spar and ground support equipment.

At CNC Proto we specialise in the machining of non-ferrous metals, mostly 6000 and 7000 series aluminium alloys, and engineering plastics. You can see a list of our most used alloys in our Services page. If your parts require a specific aluminium alloy other than the ones listed, feel free to let us know on our Quote request form!

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