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Aluminum 7A04-T6 vs 7A04-T7351

Aluminum · 7A04 temper comparison

7A04-T6 and 7A04-T7351 are two conditions of the same aluminum grade, 7A04: T6 (solution heat treated and artificially aged) versus T7351 (T73, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. 7A04-T6 is the stronger of the two: yield strength 475 MPa (68.9 ksi) against 420 MPa (60.9 ksi) for 7A04-T7351, about 13% more; tensile strength follows at 545 MPa (79 ksi) vs 490 MPa (71.1 ksi). In exchange, 7A04-T7351 is the more ductile: elongation 9% versus 8% for 7A04-T6, and 7A04-T6 is harder (150 HB vs 132 HB). 7A04-T7351 runs hotter in service (150°C vs 120°C continuous) and 7A04-T7351 conducts heat better (155 W/m·K vs 130 W/m·K).

7A04-T6Choose it when strength drives the design.

7A04-T7351Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

7A04-T6 vs 7A04-T7351: properties

7A04-T67A04-T7351

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

545 MPa79 ksi
490 MPa71.1 ksi

Yield Strength (0.2% offset)

475 MPa68.9 ksi
420 MPa60.9 ksi

Elongation at Break

8%
9%

Compressive Strength

490 MPa71.1 ksi
430 MPa62.4 ksi

Shear Strength

330 MPa47.9 ksi
290 MPa42.1 ksi

Fatigue Strength (Endurance Limit)

160 MPa23.2 ksi
148 MPa21.5 ksi

Fracture Toughness (K_IC)

27 MPa·√m24.6 ksi·√in
33 MPa·√m30 ksi·√in

Hardness, Brinell

150 HB
132 HB

Hardness, Rockwell B

87 HRB
77 HRB

Hardness, Vickers

160 HV
139 HV

Same in both: Elastic (Young's) Modulus 71 GPa10.3 Msi · Shear Modulus 26.9 GPa3.9 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Same in both: Density 2.85 g/cm³0.1 lb/in³ · Melting Point (Solidus) 477°C891 °F · Liquidus Temperature 635°C1,175 °F

Thermal

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

Thermal Conductivity

130 W/m·K75.1 BTU/hr·ft·°F
155 W/m·K89.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
150°C302 °F

Same in both: Specific Heat Capacity 960 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23.4 µm/m·K13 µin/in·°F · Latent Heat of Fusion 390 J/g168 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

33 % IACS
40 % IACS

Electrical Resistivity

5.2×10⁻⁸ Ω·m2.05 µΩ·in
4.3×10⁻⁸ Ω·m1.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

35 / 100
52 / 100

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

72 / 100
73 / 100

Formability (cold)

25 / 100
30 / 100

Same in both: Weldability 20 / 100 · Brazeability / Solderability 15 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 14 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 10%

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 scale7A04

7A04-T6 vs 7A04-T7351 — frequently asked

Is 7A04-T6 stronger than 7A04-T7351?

Yes. 7A04-T6 has a typical yield strength of 475 MPa (68.9 ksi) against 420 MPa (60.9 ksi) for 7A04-T7351 — about 13% more. Tensile strength is 545 MPa (79 ksi) vs 490 MPa (71.1 ksi).

Which condition does FabDigit quote by default, T6 or T7351?

T6 is the default 7A04 condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

When should I choose 7A04-T6 over 7A04-T7351?

Pick 7A04-T6 when strength drives the design. Pick 7A04-T7351 when the part is bent, formed or impact-loaded, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7A04-T6 and 7A04-T7351 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.