Aluminium vs stainless vs mild steel: choosing a sheet material
Weight, strength, corrosion, finish and cost — how to pick the right sheet metal for your fabrication.
Mild steel
Strong, easy to cut, bend and weld, and the lowest cost of the three. It rusts if left bare, so it is usually powder coated, painted or galvanised. A good default for brackets, frames, guards and enclosures that will be finished.
Stainless steel
Corrosion resistant without coating and easy to keep clean, which is why it's used for food, pharmaceutical and architectural work. It costs more than mild steel and needs care when welding to avoid discolouration. Can be left grained or polished.
Aluminium
Roughly a third of the weight of steel and naturally corrosion resistant. Ideal where weight matters — vehicle parts, portable equipment, fascias. It is softer, needs specialist welding skill (TIG is common) and suits anodising or powder coating.
Quick comparison
- Lowest cost: mild steel.
- Lightest: aluminium.
- Best corrosion resistance without coating: stainless steel (grade 316 for harsh environments).
- Easiest to weld: mild steel.
- Best 'as-made' appearance: stainless or anodised aluminium.
Need help deciding?
We work with all three, plus tin and copper, from 0.5 to 20 mm. Tell us how the part will be used and we'll recommend a material when we quote.