Aluminium, steel
or stainless steel?
Updated:
The three most important enclosure materials compared directly: corrosion protection, weight, strength, cost and use — and which material is right for an electrical enclosure, an outdoor enclosure or a hygiene environment.
The three most important enclosure materials
Whether electrical enclosure, server rack or outdoor enclosure — the material determines corrosion protection, weight, load-bearing capacity and cost. ZPAS manufactures in all three materials because each has clear strengths. Here is a direct comparison.
| Criterion | Sheet steel | Aluminium | Stainless steel (1.4301) |
|---|---|---|---|
| Corrosion protection | Good, thanks to powder coating/galvanising | Very good (natural oxide layer) | Excellent, even with salt air & chemicals |
| Weight | High | Low (approx. 1/3 of steel) | High |
| Strength / load capacity | Very high (Z-SERVER: 1,600 kg on levelling feet) | High, impact-resistant to IK10 | Very high |
| Typical IP rating | IP 54 / IP 55 | IP 54 / IP 55 (outdoor) | up to IP 65 |
| Finish | Powder-coated, any RAL colour | Anodised/powder-coated | Ground, smooth, easy to clean |
| Suitability for hygiene areas | Limited | Limited | Optimal (pharma, food) |
| Relative cost | Low | Medium | High |
| Typical application | Indoors: machinery, energy and automation technology | Outdoors: telecoms, energy, transport, BESS | Hygiene, chemicals, coast/offshore |
| ZPAS series | SZE2 · SZE3 · SWN · PSL | SZD (outdoor) | SWN INOX · on request |
Sheet steel — the robust standard for indoor use
Powder-coated sheet steel is the most widely used material in panel building. It offers the best balance of strength, load capacity and price and conforms to IEC 62208. For indoor applications — machine building, power distribution, automation — it is the first choice. ZPAS uses sheet steel in the SZE2, SZE3, SWN and PSL series, as standard in RAL 7035 and in any other RAL colour.
Strengths: high load capacity (Z-SERVER static 1,600 kg on levelling feet, load evenly distributed), low cost, any RAL colour, best availability. Limitations: heavier than aluminium; for permanent outdoor use only with a suitable coating.
Aluminium — lightweight & corrosion-resistant for outdoor use
Aluminium forms a natural oxide layer and does not rust — ideal for permanent outdoor use without elaborate after-treatment. It weighs only about a third as much as steel, which makes wall, pole and foundation mounting easier, and it is impact-resistant to IK10. ZPAS manufactures the SZD series outdoor enclosures from aluminium: IP 54 (IP 55 on request), −40 to +70 °C, single- or double-walled.
Strengths: corrosion-resistant, lightweight, impact-resistant, good thermal conductivity (supports heat dissipation). Limitations: more expensive than steel; lower load capacity than stainless steel.
Stainless steel — for hygiene, chemicals & salt air
Stainless steel 1.4301 (AISI 304) is the most corrosion-resistant of the three materials. Its smooth, crevice-free surface is easy to clean and sterilise — essential in pharmaceutical, food and chemical environments and in salt air on the coast or offshore. For these applications ZPAS supplies the SWN Inox stainless steel wall-mounted enclosure (IP 65, AISI 304/316) as well as made-to-measure stainless steel outdoor cabinets.
Strengths: highest corrosion and chemical resistance, hygienic, very durable. Limitations: highest price, high weight.
Which material for which application?
- Indoors, machinery/energy technology → sheet steel (SZE2/SZE3)
- Outdoors, telecoms/energy/transport/battery storage → aluminium (SZD)
- Hygiene, chemicals, coast/offshore → stainless steel 1.4301
- Maximum load capacity on a small budget → sheet steel
- Lightweight & low-maintenance outdoors → aluminium
More on this topic: IP54 or IP55 — the difference · Single-walled or double-walled? · Corrosion protection for enclosures
Not sure which material suits your application?
ZPAS manufactures in steel, aluminium and stainless steel — direct from the factory, in any special size. Describe your application and we will recommend the right material.
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