Aluminum 6061-T6 vs 7075-T6
Aluminum · grade comparison
Aluminum 6061-T6 and 7075-T6 are both aluminum grades, compared here in the T6 condition. 7075-T6 is the stronger of the two: yield strength 503 MPa (73 ksi) against 276 MPa (40 ksi) for 6061-T6, about 82% more; tensile strength follows at 572 MPa (83 ksi) vs 310 MPa (45 ksi). 7075-T6 is harder — 150 HB against 95 HB for 6061-T6 — which matters for wear surfaces and threads. 6061-T6 is lighter (2.7 g/cm³ vs 2.81 g/cm³ for 7075-T6) and 6061-T6 runs hotter in service (170°C vs 120°C continuous). On the shop floor, 6061-T6 welds better (excellent vs poor), 6061-T6 forms better (fair vs poor), and 6061-T6 sits in a lower cost tier (budget, $) than 7075-T6 (premium, $$$).
6061-T6Choose it when weight is the constraint, or when the part sees heat.
7075-T6Choose it when strength drives the design, or when surface hardness matters.
Buyer's decision notes
Choose 6061-T6 for a broadly available machined or fabricated aluminum part when weldability, anodizing response and a forgiving supply chain matter. Choose 7075-T6 when the design earns value from its higher strength and can accommodate the alloy’s welding, corrosion and condition-control constraints.
Compare the same condition
T6 identifies a heat-treatment sequence, but it does not identify product form, stress relief or test direction. Compare plate with plate or bar with bar at the drawing thickness; a stress-relieved T651 or T6511 product should not be silently treated as interchangeable with generic T6 stock.
- Machining and movement
- Both alloys machine well, but a thin or heavily pocketed part can move when residual stress is released. Ask for the actual mill product and stress-relieved condition, then plan roughing, stabilization and final cuts around the finished geometry.
- Joining strategy
- 6061 is commonly fusion welded with an engineered filler and post-weld property plan. Do not carry that assumption into a 7075-T6 structure; use mechanical fastening or a qualified joining route unless the design authority has approved the weld and its resulting properties.
- Finish and corrosion
- Anodize color and appearance depend on alloy, temper, surface preparation and lot. Keep cosmetic panels on a controlled alloy and mill lot where color matching matters, and evaluate 7075 corrosion or stress-corrosion exposure in the actual assembly rather than from strength alone.
- Condition choice
- If 7075-T6 does not provide the required corrosion or stress-corrosion margin, review an overaged condition such as T73 with the responsible engineer. Treat that as a new material condition with its own allowable properties, not a finish substitution.
Put this on the RFQ
- State alloy, exact temper, product form, thickness or diameter, applicable material specification and grain direction where it affects the part.
- Identify welds, critical fatigue or stress-corrosion locations, anodized cosmetic faces and any requirement for one mill lot.
- For distortion-sensitive machining, request a stress-relieved product condition and agree the rough-machine, stabilize and finish-machine sequence.
Primary references
- Kaiser Aluminum — 6061 sheet and plate — Producer datasheet for 6061 flat-rolled products, including T6 and T651 fabrication ratings and typical properties.
- Kaiser Aluminum — 7075 sheet and plate — Producer datasheet distinguishing 7075 T6-family and overaged flat-rolled conditions, fabrication ratings and typical properties.
- ASTM — B209/B209M — Current sheet-and-plate specification defining covered alloys, tempers, product forms and ordering requirements.
FabDigit resources: 6061-T6 datasheet, 7075-T6 datasheet, CNC design guide and sheet-metal design guide.
6061-T6 vs 7075-T6: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Latent Heat of Fusion
Max Service Temperature (continuous)
Same in both: Thermal Expansion (CTE, 20–100 °C) 23.6 µm/m·K13.1 µin/in·°F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Brazeability / Solderability
Machinability Rating (AISI 1212 = 100 %)
Same in both: Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 25.5 MN·m/kg
Strength versus weight
Yield strength against density for every aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 6061-T6 | 7075-T6 |
|---|---|---|
| Default condition | T6 | T6 |
| Relative cost | $ Budget | $$$ Premium |
| Min. machined wall | 0.5 mm | 0.8 mm |
| Best machined surface | Ra 0.8 µm | Ra 0.8 µm |
Both are offered for CNC machining and Sheet metal. Both take the same 16 finishes: Anodizing Type II, Cerakote, Chem Film (Alodine), DLC, E-Coating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Nickel Plating and 4 more.
6061-T6 vs 7075-T6 — frequently asked
Is 7075-T6 stronger than 6061-T6?
Yes. 7075-T6 has a typical yield strength of 503 MPa (73 ksi) against 276 MPa (40 ksi) for 6061-T6 — about 82% more. Tensile strength is 572 MPa (83 ksi) vs 310 MPa (45 ksi).
Which is cheaper, 6061-T6 or 7075-T6?
6061-T6 is the lower-cost material: it sits in the budget tier ($) while 7075-T6 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, 6061-T6 or 7075-T6?
7075-T6, by a small margin. Both rate very good for machinability — 78/100 against 70/100 for 6061-T6; for welding the order is 6061-T6 first (excellent, 85/100) then 7075-T6 (poor, 18/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 6061-T6 and 7075-T6 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.