FabDigitFabDigit

Aluminum 7072 vs 7129

Aluminum · grade comparison

Aluminum 7072 and 7129 are both aluminum grades. 7129 is the stronger of the two: yield strength 350 MPa (50.8 ksi) against 21 MPa (3.05 ksi) for 7072, about 17 times as much; tensile strength follows at 400 MPa (58 ksi) vs 55 MPa (7.98 ksi). In exchange, 7072 is the more ductile: elongation 32% versus 11% for 7129, and 7129 is harder (120 HB vs 20 HB). 7072 runs hotter in service (150°C vs 120°C continuous) and 7072 conducts heat better (227 W/m·K vs 155 W/m·K). On the shop floor, 7129 machines more easily (good vs poor), 7072 welds better (very good vs poor), and 7072 sits in a lower cost tier (budget, $) than 7129 (premium, $$$).

7072Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

7129Choose it when strength drives the design, or when the part is machined in volume.

7072 vs 7129: properties

70727129

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

69 GPa10 Msi
70 GPa10.2 Msi

Shear Modulus

26 GPa3.8 Msi
26.5 GPa3.8 Msi

Bulk Modulus

69 GPa10 Msi
70 GPa10.2 Msi

Tensile Strength (Ultimate)

55 MPa8 ksi
400 MPa58 ksi

Yield Strength (0.2% offset)

21 MPa3 ksi
350 MPa50.8 ksi

Elongation at Break

32%
11%

Shear Strength

41 MPa5.9 ksi
235 MPa34.1 ksi

Fatigue Strength (Endurance Limit)

30 MPa4.4 ksi
150 MPa21.8 ksi

Hardness, Brinell

20 HB
120 HB

Compressive Strength

—
355 MPa51.5 ksi

Fracture Toughness (K_IC)

—
30 MPa·√m27.3 ksi·√in

Hardness, Vickers

—
130 HV

Same in both: Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

640°C1,184 °F
480°C896 °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
155 W/m·K89.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

23.6 µm/m·K13.1 µin/in·°F
23.4 µm/m·K13 µin/in·°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: Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

60 % IACS
32 % IACS

Electrical Resistivity

2.87×10⁻⁸ Ω·m1.13 µΩ·in
5.4×10⁻⁸ Ω·m2.13 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.96 V
-0.84 V

Corrosion Resistance

72 / 100
40 / 100

Manufacturability

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

Machinability

30 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
70%

Weldability

80 / 100
30 / 100

Formability (cold)

95 / 100
35 / 100

Brazeability / Solderability

80 / 100
15 / 100

Polishability

45 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

200 MJ/kg85,985 BTU/lb
205 MJ/kg88,134 BTU/lb

Embodied Carbon (primary production)

13 kg CO₂/kg
12.5 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

20%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

20 kN·m/kg
143 kN·m/kg

Specific Stiffness (E / density)

25.4 MN·m/kg
25 MN·m/kg

Modulus of Resilience

3 kJ/m³
875 kJ/m³

Thermal Diffusivity

92.7 mm²/s
64 mm²/s

Thermal Shock Resistance Index

8
38

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 scale70727129

Manufacturing and finishing

Capability70727129
Sheet metalYes—
Default condition——
Relative cost$ Budget$$$ Premium
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 7129 — frequently asked

Is 7129 stronger than 7072?

Yes. 7129 has a typical yield strength of 350 MPa (50.8 ksi) against 21 MPa (3.05 ksi) for 7072 — about 17 times as much. Tensile strength is 400 MPa (58 ksi) vs 55 MPa (7.98 ksi).

Which is cheaper, 7072 or 7129?

7072 is the lower-cost material: it sits in the budget tier ($) while 7129 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, 7072 or 7129?

7129. Its machinability rates good (62/100) against poor (30/100) for 7072; for welding the order is 7072 first (very good, 80/100) then 7129 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7072 and 7129 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.