ALLOY COMPARISON
6061 vs 7075 aluminum: which alloy for your part?
The two forging alloys that dominate structural aluminum — compared honestly on strength, corrosion, machinability and cost, from a shop that forges both every day.
Side by side
| Property (T6) | 6061 | 7075 |
|---|---|---|
| Tensile strength | 310 MPa | 572 MPa |
| Yield strength | 276 MPa | 503 MPa |
| Density | 2.70 g/cm³ | 2.81 g/cm³ |
| Corrosion resistance | Excellent | Good (anodise for service) |
| Weldability | Good | Poor — design one-piece |
| Anodised finish | Uniform, cosmetic-grade | Slightly yellow-grey tone |
| Material cost | Lower | Higher (Zn, Cu content) |
| Best for | General structural, cyclic loads | High-load, weight-critical parts |
Choose 6061 when…
Cost is the design driver
Same forging process, lower material cost — the default for structural parts that 6061’s numbers already cover.
Cosmetic anodising matters
Uniform colour and finish; the industry choice for visible bicycle components.
The part gets welded downstream
6061 tolerates welding; 7075 does not.
Full data: 6061 properties page
Choose 7075 when…
Loads are near 6061’s ceiling
572 MPa tensile buys real margin in compact sections.
Weight is priced
More strength per gram for high-end mobility and aerospace-style parts.
Wear surfaces exist
Hard-anodised 7075 resists galling and wear.
Full data: 7075 properties page
One more option: 6082
European drawings often specify EN AW-6082 — slightly stronger than 6061, equally forgeable, standard across the EU. If your customer base is European, 6082 may already be your spec. We forge all four alloys (6061/6063/6082/7075) with per-batch mill certificates.
FAQ
Common questions
Is 7075 stronger than 6061?
Yes — roughly 84% higher tensile strength (572 vs 310 MPa) and much higher yield. That is why 7075 is called aircraft-grade.
Is 6061 cheaper than 7075?
Yes — 6061 is the economical default. 7075’s zinc and copper content raise material and machining cost, so it is specified only where strength-to-weight earns it.
Which welds better?
6061 welds well (with some strength loss in the weld zone). 7075 is generally not welded — its high-strength temper degrades badly, so designs use one-piece forgings instead.
Which anodises better?
Both anodise, but 6061 gives a more uniform cosmetic finish. 7075 anodises to a slightly yellow-grey tone; hard anodising is common for wear parts.
Which is better for bicycle parts?
Cranksets and general structural parts: 6061-T6. High-load interfaces where weight matters: 7075-T6. Our cranksets run 6061-T6 because fatigue at volume is the design driver — see forged cranksets.
Does 7075 corrode faster?
It is more corrosion-sensitive than 6061, especially against stress corrosion. Type II/III anodising is the standard mitigation — we anodise in-house.
Can both be forged to T6?
Yes. Both are hot-forged then solution-treated and aged. Forging aligns grain before heat treatment — see 6061 and 7075 pages.
What about 6082?
6082 sits near 6061 with slightly higher strength and is the European (EN) designation of choice — a frequent spec on EU drawings. We forge it routinely.
Which should I choose for my part?
If the drawing already says, use it. If not: 6061 unless a load calculation says the part needs 7075’s strength — an engineer confirms either way in the free drawing review.
Can you forge both in one order?
Yes — mixed-alloy programs are routine; every batch carries its own mill certificate.
MATERIAL GUIDES
6061 properties · 7075 properties · 6061 vs 7075 · What is billet aluminum · Forging vs casting · Forged blanks vs billet
Not sure which alloy your part needs?
Send the drawing — an engineer recommends the alloy honestly and quotes both options within 3 working days.