How to choose the right aluminium alloy
More than 540 registered compositions. I’m talking about the number of aluminium alloys that are available today. Do you know how to choose the one for your product?
Aluminium can be alloyed with other metals and non-metals. This allows the aluminium to take on different properties. Iron (Fe) and silicon (Si) are naturally found in the aluminium, from the bauxite, and are in virtually all technically used aluminium materials.
Aluminium that contains as much as 1 percent by weight, of iron and silicon together, is called unalloyed or pure aluminium.
Unalloyed aluminium is soft and has low strength, and its use is limited. Alloyed aluminium, on the other hand, has increased mechanical properties and can therefore be used in many different contexts.
Common alloying substances, beyond iron and silicon, are magnesium (Mg), manganese (Mn), copper (Cu) and zinc (Zn).
An outstanding aluminium company needs to have metallurgical competence and the ability to make sure the alloy composition can be produced in a repeatable and consistent way – and that the alloy actually achieves what we want it to achieve.
Finding the right alloy
But let me get back to the main question: How do you choose the right alloy for your product? There are, as I mentioned, more than 540 registered alloys.
Start by specifying your needs. Here are some properties to consider:
- Strength
- Surface finish
- Suitability for decorative anodizing
- Corrosion resistance
- Machinability
- Weldability
- Production economics – price
You can find lists and guides on the internet – consider the source! – where alloy families are graded according to these characteristics, and you can also find recommendations. This will help you get closer to the right alloy.
But be aware that not all alloy compositions are found on all the lists. My advice: Do your homework and then talk to an expert.
