Before diving into the data, it helps to understand what these three alloys are chemically and how that determines their behaviour.
| Property | 5052 (Al-Mg) | 6061 (Al-Mg-Si) | 7075 (Al-Zn-Mg-Cu) |
|---|---|---|---|
| Alloy Family | 5xxx — Non-heat-treatable | 6xxx — Heat-treatable | 7xxx — Heat-treatable |
| Primary Alloying Elements | 2.2–2.8% Mg, 0.25% Cr | 0.8–1.2% Mg, 0.4–0.8% Si | 5.1–6.1% Zn, 2.1–2.9% Mg, 1.2–2.0% Cu |
| Strengthening Mechanism | Strain hardening (cold work) | Solution + age hardening (T4/T6) | Solution + age hardening (T6/T73) |
| Common Tempers | O, H32, H34, H38 | T4, T6, T651 | T6, T651, T73 |
| Relative Cost Index | 1.0x (baseline) | 1.1–1.3x | 2.0–3.0x |
Key insight: 5052 cannot be heat treated — you cannot make it stronger by quenching and aging. Its strength is set at the rolling mill. 6061 and 7075 both respond to T6 heat treatment, but 7075's higher zinc content gives it roughly 85% higher tensile strength than 6061-T6 — at the cost of significantly reduced corrosion resistance and weldability.
All data below reflects the most common commercial temper for each alloy. Values are representative and may vary slightly by supplier and thickness.
| Property | 5052-H32 | 6061-T6 | 7075-T6 |
|---|---|---|---|
| Tensile Strength (MPa) | 228 | 310 | 572 |
| Tensile Strength (ksi) | 33 | 45 | 83 |
| Yield Strength (MPa) | 193 | 276 | 503 |
| Yield Strength (ksi) | 28 | 40 | 73 |
| Elongation at Break (%) | 12 | 12–17 | 11 |
| Hardness (Brinell) | 60 | 95 | 150 |
| Modulus of Elasticity (GPa) | 70.3 | 68.9 | 71.7 |
| Fatigue Strength (MPa, 5×10⁸ cycles) | 117 | 96.5 | 159 |
| Density (g/cm³) | 2.68 | 2.70 | 2.81 |
| Thermal Conductivity (W/m·K) | 138 | 167 | 130 |
7075-T6 is in a different league mechanically — nearly 85% stronger in yield and 60% harder than 6061-T6. But notice its thermal conductivity is lower than 6061, and its density is 4% higher due to the heavier zinc atoms in its matrix.
Bottom line: Choose 5052 when corrosion resistance, formability, or weldability matter more than raw strength. It is the safest choice for any marine or chemical exposure application.
Bottom line: When in doubt, pick 6061-T6. It is the default choice for 80% of engineering and fabrication applications. Only deviate when you specifically need 5052's corrosion resistance and formability, or 7075's extreme strength.
Bottom line: 7075 is a specialist alloy. Use it when the primary requirement is maximum strength and stiffness at minimum weight, and when the part will be used in a controlled environment (indoor, dry, or protected). Never use 7075 in marine, chemical, or outdoor uncoated applications.
| Decision Factor | Winner | Why |
|---|---|---|
| Tensile Strength | 7075-T6 (572 MPa) | 85% stronger than 6061-T6, 150% stronger than 5052-H32 |
| Yield Strength | 7075-T6 (503 MPa) | 82% higher yield than 6061-T6, 160% higher than 5052-H32 |
| Corrosion Resistance | 5052-H32 | 5052: excellent. 6061: good (needs coating in saltwater). 7075: poor (must be coated) |
| Weldability | 5052/6061 (tie) | Both weld well with standard methods. 7075 is effectively unweldable by fusion |
| Formability (bending, drawing) | 5052-H32 | Best bend radius, deepest draw, lowest springback. 6061-T6 cracks on tight bends |
| Machinability | 6061-T6 | Best chip control, surface finish, and tool life. 7075 close second. 5052 worst (gummy) |
| Fatigue Strength | 7075-T6 (159 MPa) | 7075 leads. 5052 (117 MPa) beats 6061 (96.5 MPa) despite lower static strength |
| Cost-Effectiveness | 6061-T6 | Best strength-per-dollar. Widest availability and lowest lead time |
| Marine Suitability | 5052-H32 | Only one truly marine-safe. 6061 acceptable inland only. 7075 never |
| Anodizing Quality | 5052/6061 (tie) | Both anodize well. 7075 can anodize but copper content produces darker, less consistent colors |
Follow these four questions in order to narrow down to the right alloy:
If your application is aerospace, high-performance racing, or precision tooling where every gram matters and loads are high → 7075-T6/T651. Otherwise, proceed to Step 2.
If yes → 5052-H32 (or 5083 for thick plate). If no (indoor or dry environment) → proceed to Step 3.
If you are bending tight radii, deep-drawing, or spinning → 5052-H32 (or 6061-T4 if you will heat-treat after forming). For general fabrication with moderate forming → proceed to Step 4.
If you need to weld, machine, and assemble at reasonable cost → 6061-T6/T651. For non-welded, high-volume machined parts where strength matters less than cost → 6061-T6 is still your best bet.
| Your Priority | Best Choice | Runner-Up |
|---|---|---|
| Maximum strength (structural / aerospace) | 7075-T6 | 6061-T6 (if budget-limited) |
| Marine / saltwater exposure | 5052-H32 | 5083 if available (higher strength) |
| Welded assemblies | 5052-H32 | 6061-T6 |
| CNC machining / tight tolerances | 6061-T651 | 7075-T651 (for higher strength) |
| Deep drawing / complex forming | 5052-O or H32 | 6061-O (then heat treat) |
| Best value / general engineering | 6061-T6 | — |
| Chemical storage / food contact | 5052-H32 | 3003 if lower cost needed |
| Best fatigue life (cyclic loading) | 7075-T6 | 5052-H32 |
Yes, but the results are less consistent than 5052 or 6061. The copper content in 7075 produces darker anodized finishes, and achieving uniform color is more difficult. For decorative anodizing, 6061 or 5052 are preferred. For functional (hard coat) anodizing, 7075 performs well and benefits significantly from the added corrosion protection.
5052 in H32 or O temper is best for tight-radius bending. It can be bent to an inside radius as tight as 1× material thickness without cracking. 6061-T6 requires a larger bend radius (2–3× thickness) and may crack on sharp bends. 7075-T6 should not be bent — its low ductility makes it prone to fracture under bending stress.
ER4043 (Al-Si) and ER5356 (Al-Mg) are the most common fillers for 6061. ER4043 offers better fluidity and crack resistance, making it easier for general fabrication. ER5356 produces slightly higher weld strength and better anodizing color match, so it is preferred when the assembly will be anodized after welding.
7075-T6 has a tensile strength of 572 MPa, which is comparable to mild steel (A36 at 400–550 MPa) but below high-strength steels (1000+ MPa). However, 7075 is about one-third the density of steel, giving it a superior strength-to-weight ratio. Per kilogram, 7075 carries more load than most steels — that is why aerospace uses it, not because it is absolutely stronger.
T651 is a T6 temper that has been stress-relieved by stretching (1–3% permanent stretch) after solution heat treatment and before aging. This reduces residual stresses that cause warping during machining. Use T651 for thick plates that will be heavily machined — it holds tighter flatness tolerances than standard T6. For thin sheet or simple shapes, standard T6 is sufficient.
Choosing between 5052, 6061, and 7075 aluminum does not have to be complicated. Remember the three-word summary:
If you are still unsure, start with 6061-T6. It is the most forgiving alloy for first-time selection and works well for the majority of structural, machined, and fabricated parts. Move to 5052 only when corrosion or forming demands it. Move to 7075 only when strength requirements exceed what 6061 can deliver — and be prepared for the trade-offs in cost, corrosion protection, and joining methods.
At FANY LASER, we supply 5052, 6061, and 7075 aluminum in sheet, plate, and tube forms — cut to your specifications with fast lead times. Whether you need laser-cut blanks, precision-sawn plates, or custom-sized sheets, our team can help you select the right grade and temper for your project.
