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Aluminum 7072 vs 7A85

Aluminum · grade comparison

Aluminum 7072 and 7A85 are both aluminum grades. 7A85 is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 21 MPa (3.05 ksi) for 7072, about 22 times as much; tensile strength follows at 510 MPa (74 ksi) vs 55 MPa (7.98 ksi). In exchange, 7072 is the more ductile: elongation 32% versus 10% for 7A85, and 7A85 is harder (155 HB vs 20 HB). 7072 is lighter (2.72 g/cm³ vs 2.85 g/cm³ for 7A85) and 7072 runs hotter in service (150°C vs 120°C continuous). On the shop floor, 7A85 machines more easily (very good vs poor), 7072 welds better (very good vs poor), and 7072 sits in a lower cost tier (budget, $) than 7A85 (high, $$$$).

7072Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

7A85Choose it when strength drives the design, or when the part is machined in volume.

7072 vs 7A85: properties

70727A85

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

69 GPa10 Msi
71 GPa10.3 Msi

Shear Modulus

26 GPa3.8 Msi
26.9 GPa3.9 Msi

Bulk Modulus

69 GPa10 Msi
75 GPa10.9 Msi

Tensile Strength (Ultimate)

55 MPa8 ksi
510 MPa74 ksi

Yield Strength (0.2% offset)

21 MPa3 ksi
470 MPa68.2 ksi

Elongation at Break

32%
10%

Shear Strength

41 MPa5.9 ksi
300 MPa43.5 ksi

Fatigue Strength (Endurance Limit)

30 MPa4.4 ksi
160 MPa23.2 ksi

Hardness, Brinell

20 HB
155 HB

Reduction in Area

—
22%

Compressive Strength

—
480 MPa69.6 ksi

Fracture Toughness (K_IC)

—
40 MPa·√m36.4 ksi·√in

Hardness, Vickers

—
165 HV

Same in both: Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

640°C1,184 °F
476°C889 °F

Liquidus Temperature

657°C1,215 °F
635°C1,175 °F

Thermal

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

Thermal Conductivity

227 W/m·K131 BTU/hr·ft·°F
150 W/m·K86.7 BTU/hr·ft·°F

Specific Heat Capacity

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

Latent Heat of Fusion

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

Max Service Temperature (continuous)

150°C302 °F
120°C248 °F

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

60 % IACS
40 % IACS

Electrical Resistivity

2.87×10⁻⁸ Ω·m1.13 µΩ·in
4.3×10⁻⁸ Ω·m1.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.96 V
-0.82 V

Corrosion Resistance

72 / 100
48 / 100

Manufacturability

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

Machinability

30 / 100
72 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
190%

Weldability

80 / 100
20 / 100

Formability (cold)

95 / 100
25 / 100

Brazeability / Solderability

80 / 100
10 / 100

Polishability

45 / 100
60 / 100

Castability

—
30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

200 MJ/kg85,985 BTU/lb
210 MJ/kg90,284 BTU/lb

Embodied Water

1,200 L/kg144 gal/lb
1,100 L/kg132 gal/lb

Typical Recycled Content

20%
5%

Same in both: Embodied Carbon (primary production) 13 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

20 kN·m/kg
179 kN·m/kg

Specific Stiffness (E / density)

25.4 MN·m/kg
24.9 MN·m/kg

Modulus of Resilience

3 kJ/m³
1,556 kJ/m³

Thermal Diffusivity

92.7 mm²/s
61.2 mm²/s

Thermal Shock Resistance Index

8
46

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 scale70727A85

Manufacturing and finishing

Capability70727A85
Sheet metalYes—
Default condition——
Relative cost$ Budget$$$$ High
Min. machined wall——
Best machined surface——
Anodizing Type IIYes—
CerakoteYes—
Chem Film (Alodine)Yes—
E-CoatingYes—
ElectropolishingYes—
Hard Anodize Type III w/ PTFEYes—
Hard Anodizing Type IIIYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Powder CoatingYes—

They share 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.

7072 vs 7A85 — frequently asked

Is 7A85 stronger than 7072?

Yes. 7A85 has a typical yield strength of 470 MPa (68.2 ksi) against 21 MPa (3.05 ksi) for 7072 — about 22 times as much. Tensile strength is 510 MPa (74 ksi) vs 55 MPa (7.98 ksi).

Which is cheaper, 7072 or 7A85?

7072 is the lower-cost material: it sits in the budget tier ($) while 7A85 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, 7072 or 7A85?

7A85. Its machinability rates very good (72/100) against poor (30/100) for 7072; for welding the order is 7072 first (very good, 80/100) then 7A85 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7072 and 7A85 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.