6061 vs 7075 Aluminum
6061 is the general-purpose aluminum — weldable, corrosion-resistant, easy to find. 7075 is the high-strength aerospace alloy — nearly twice as strong in T6, but poorly weldable and less corrosion resistant. The choice comes down to whether you need maximum strength or weldability and cost.
| Property | 6061-T6 | 7075-T6 |
|---|---|---|
| Alloy family | 6xxx (Mg-Si) | 7xxx (Zn) |
| Tensile (T6) | 310 MPa (45 ksi) | 572 MPa (83 ksi) |
| Yield (T6) | 276 MPa (40 ksi) | 503 MPa (73 ksi) |
| Density | 2.70 g/cm³ | 2.81 g/cm³ |
| Elongation (T6) | 12–17% | 9–11% |
| Hardness | ~95 HB | ~150 HB |
| Weldability | Good | Poor (fusion welding) |
| Corrosion resistance | Good | Lower — often anodized/clad |
| Relative cost | Baseline | Higher |
| Typical uses | Structural, frames, general fab | Aerospace, high-stress parts, molds |
Values for the T6 temper; properties vary with temper and product form. Confirm against the mill certificate.
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Find suppliersFrequently asked questions
- Is 7075 stronger than 6061?
- Yes — substantially. In the T6 temper 7075 has roughly double the tensile and yield strength of 6061 (≈572 vs 310 MPa tensile). 7075 is the high-strength aerospace alloy; 6061 is the general-purpose workhorse.
- Which is more weldable?
- 6061 by far. It welds readily (commonly with 4043/5356 filler). 7075 is considered poorly weldable by fusion — its high zinc content causes hot cracking — so 7075 parts are usually fastened or bonded rather than welded.
- When should I use 6061?
- Most of the time: structural shapes, frames, brackets, enclosures, and anything you need to weld or that benefits from better corrosion resistance and lower cost. Reach for 7075 only when you need maximum strength-to-weight and can fasten rather than weld.