Which Aluminium Alloy Do I Need for My Project?

Choosing the right aluminium alloy for your project can feel like a bit of a puzzle. Every aluminium alloy brings something different to the table—whether it’s strength, corrosion resistance, or even how easy it is to work with. At Simmal, we know how important it is to pick the right one, so we’ve put together this guide to help you make the right choice.

Important Things to Consider in Alloy Selection

When choosing an aluminium alloy, you need to consider a few things. First of all, strength, which is the ability to withstand loads. High-strength alloys like the 2000 series (e.g.2024-T351) or 7000 series (e.g. 7075-T6) have extremely high strength-to-weight ratios, whereas near-pure aluminium, the 1000 series (e.g 1050A), is very soft. Then you also need to think about machinability, which is how easily the alloy can be cut, drilled, or milled. Some alloys form short chips and machine very well, for example, the 2011 alloy or 6082 alloy, while others, such as 1050 or 5083, are gummy or abrasive to tooling. Weldability is another thing to consider. Can the alloy withstand high heat without cracking or losing strength? Alloys with high copper or zinc, like most of the 2000 series (apart from the 2219 series) and 7000 series, tend to crack when welded, whereas 5000 series and many 6000 series can weld very well.

Which Alloy Do I Need for My Industry?

Different industries need different things from their aluminium, so we’re going to break down recommendations by industry.

Construction Industry

In construction, aluminium is mainly used in things like frames, beams, cladding, and fascias. So, it will require moderate to high strength, good corrosion resistance, and weldability. Ease of extruding complex shapes and a good surface finish for architectural appeal are also important. The construction sector predominantly uses 6000-series alloys for extruded components. In particular, the 6082-T6 alloy is a top choice for load-bearing structures, whereas 6063-T6 is used for architectural sections like window frames and curtain wall mullions. For roofing and cladding, you want something that will have high corrosion resistance, like marine-grade 5000 series sheets such as 5083 or 5251 alloys.

Aerospace Industry

Aerospace projects demand a maximum strength-to-weight ratio. Every gram matters, so high-strength alloys dominate for airframes, wings, and engine parts. Machinability is important for precise components, but weldability is less important because aircraft structures are often riveted or bolted. Corrosion resistance is also managed by additional surface treatments like anodising or chemical conversion coatings and passivation such as Chromate Conversion Coating (CCC), or the more environmentally friendly and RoHS compliant Trivalent Chromium Conversion Coating (TCCC) , rather than relying on the alloy alone. The aerospace industry mainly uses 2000-series and 7000-series alloys for their superior strength. These alloys offer one of the highest strength-to-weight ratios among light-weight metals, with some reaching strength levels approaching lower-grade steels while maintaining significantly lower weight. 6061-T6 also appears in aerospace for secondary structures or even space applications where welding and corrosion resistance might be needed, like in aeroplane seats, fuel tanks or satellites.

Automotive Industry

In the automotive industry, the main things to consider are formability (for stamping body panels), strength (for crashworthiness of frames/chassis), weldability (for assembling components via welding or bonding), and cost. Typically, alloys from the 5000 series (e.g. alloy 5251) and 6000 series (e.g. alloy 6082) are common in automotive applications, with some speciality use of the 7000 series in performance and luxury vehicles. For body panels and structural sheet alloys like the 5754, 5182, and 5052, they are common as non-heat-treatable alloys can be easily formed into panels and then welded. For structural and crash components, 6082-T6, 6061-T6 extrusions, or forgings are used, for example, in suspension arms and bumper beams. High-performance applications utilise 7003/7005 or even 7075 for parts like wheel hubs, engine components, or roll cages in racing.

General Fabrication & Manufacturing

General fabrication covers a wide range of projects—from custom machine parts and frames to sheet-metal work, enclosures, and prototypes. This means that adaptability is key; you need an alloy that is easy to work with and has sufficient strength for general use. Most general fabrication jobs default to 6061/6082 alloy, as they have a good mix of strength and workability. For sheet work, they tend to use moderately strong, highly formable alloys like 5052/5251. For projects that involve extensive machining, a free machining alloy like 2011 or 2014 is best however 2011 has poor corrosion resistance and should not be used where exposure to moisture and chemicals is expected, and if extreme formability is needed, a pure grade like 1050 or 1100 could be used.

The team at Simmal is proud to offer expert advice backed by years of experience helping customers find exactly what they need. From structural demands in construction to the lightweight, high-strength requirements of aerospace, we can guide you toward the ideal alloy for your project. Ready to get started? Contact our team today to discuss your requirements or request a quote. We’re here to help.