FabDigitFabDigit

Aluminum 7055 vs 7075

Aluminum · grade comparison

Aluminum 7055 and 7075 are both aluminum grades. 7055 is the stronger of the two: yield strength 634 MPa (92 ksi) against 503 MPa (73 ksi) for 7075, about 26% more; tensile strength follows at 655 MPa (95 ksi) vs 572 MPa (83 ksi). 7055 is harder — 190 HB against 150 HB for 7075 — which matters for wear surfaces and threads. 7055 conducts heat better (154 W/m·K vs 130 W/m·K). On the shop floor, 7075 machines more easily (very good vs good) and 7075 sits in a lower cost tier (premium, $$$) than 7055 (high, $$$$).

7055Choose it when strength drives the design, or when surface hardness matters.

7075Choose it when the part is machined in volume, or when cost is the deciding factor.

7055 vs 7075: properties

70557075

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

70.5 GPa10.2 Msi
71.7 GPa10.4 Msi

Bulk Modulus

75 GPa10.9 Msi
70 GPa10.2 Msi

Tensile Strength (Ultimate)

655 MPa95 ksi
572 MPa83 ksi

Yield Strength (0.2% offset)

634 MPa92 ksi
503 MPa73 ksi

Compressive Strength

648 MPa94 ksi
505 MPa73.2 ksi

Shear Strength

372 MPa54 ksi
331 MPa48 ksi

Fatigue Strength (Endurance Limit)

185 MPa26.8 ksi
159 MPa23.1 ksi

Fracture Toughness (K_IC)

31 MPa·√m28.2 ksi·√in
27 MPa·√m24.6 ksi·√in

Hardness, Brinell

190 HB
150 HB

Hardness, Vickers

200 HV
175 HV

Reduction in Area

—
25%

Charpy V-Notch Impact (RT)

—
8 J5.9 ft·lbf

Hardness, Rockwell B

—
87 HRB

Same in both: Shear Modulus 26.9 GPa3.9 Msi · Poisson's Ratio 0.33 · Elongation at Break 11%

Physical

Density and transition temperatures.

Density

2.85 g/cm³0.1 lb/in³
2.81 g/cm³0.1 lb/in³

Melting Point (Solidus)

475°C887 °F
477°C891 °F

Same in both: Liquidus Temperature 635°C1,175 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

154 W/m·K89 BTU/hr·ft·°F
130 W/m·K75.1 BTU/hr·ft·°F

Specific Heat Capacity

860 J/kg·K0.21 BTU/lb·°F
960 J/kg·K0.23 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

23.4 µm/m·K13 µin/in·°F
23.6 µm/m·K13.1 µin/in·°F

Latent Heat of Fusion

390 J/g168 BTU/lb
395 J/g170 BTU/lb

Same in both: Max Service Temperature (continuous) 120°C248 °F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

37 % IACS
33 % IACS

Electrical Resistivity

4.66×10⁻⁸ Ω·m1.83 µΩ·in
5.15×10⁻⁸ Ω·m2.03 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.84 V
-0.83 V

Corrosion Resistance

42 / 100
35 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

62 / 100
78 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
160%

Weldability

15 / 100
18 / 100

Formability (cold)

20 / 100
25 / 100

Polishability

55 / 100
60 / 100

Same in both: Brazeability / Solderability 10 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

1,150 L/kg138 gal/lb
1,200 L/kg144 gal/lb

Typical Recycled Content

12%
15%

Same in both: Embodied Energy (primary production) 205 MJ/kg88,134 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

230 kN·m/kg
204 kN·m/kg

Specific Stiffness (E / density)

24.7 MN·m/kg
25.5 MN·m/kg

Modulus of Resilience

2,851 kJ/m³
1,764 kJ/m³

Thermal Diffusivity

62.8 mm²/s
48.2 mm²/s

Thermal Shock Resistance Index

61
44

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.

20501002005002.22.42.62.83Density (g/cm³)Yield strength (MPa) — log scale70757055

Manufacturing and finishing

Capability70557075
Default condition—T6
Relative cost$$$$ High$$$ Premium
Min. machined wall0.5 mm0.8 mm
Best machined surfaceRa 0.8 µmRa 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.

7055 vs 7075 — frequently asked

Is 7055 stronger than 7075?

Yes. 7055 has a typical yield strength of 634 MPa (92 ksi) against 503 MPa (73 ksi) for 7075 — about 26% more. Tensile strength is 655 MPa (95 ksi) vs 572 MPa (83 ksi).

Which is cheaper, 7055 or 7075?

7075 is the lower-cost material: it sits in the premium tier ($$$) while 7055 is high ($$$$). 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, 7055 or 7075?

7075. Its machinability rates very good (78/100) against good (62/100) for 7055.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7055 and 7075 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.