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Aluminum 7A77 As Printed vs 7A77-T73

Aluminum · 7A77 temper comparison

7A77 As Printed and 7A77-T73 are two conditions of the same aluminum grade, 7A77: As Printed (as built (as printed)) versus T73 (solution heat treated and overaged for stress-corrosion resistance). The chemistry is identical, so every difference below comes from the condition. 7A77-T73 is the stronger of the two: yield strength 400 MPa (58 ksi) against 310 MPa (45 ksi) for 7A77 As Printed, about 29% more; tensile strength follows at 470 MPa (68.2 ksi) vs 400 MPa (58 ksi). 7A77-T73 is the more ductile: elongation 8% versus 5% for 7A77 As Printed, and 7A77-T73 is harder (135 HB vs 110 HB). 7A77-T73 runs hotter in service (150°C vs 100°C continuous) and 7A77-T73 conducts heat better (150 W/m·K vs 105 W/m·K).

7A77-T73Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

7A77 As Printed vs 7A77-T73: properties

7A77 As Printed7A77-T73

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

400 MPa58 ksi
470 MPa68.2 ksi

Yield Strength (0.2% offset)

310 MPa45 ksi
400 MPa58 ksi

Elongation at Break

5%
8%

Fatigue Strength (Endurance Limit)

110 MPa16 ksi
135 MPa19.6 ksi

Fracture Toughness (K_IC)

20 MPa·√m18.2 ksi·√in
29 MPa·√m26.4 ksi·√in

Hardness, Brinell

110 HB
135 HB

Hardness, Vickers

115 HV
145 HV

Same in both: Elastic (Young's) Modulus 70 GPa10.2 Msi · Shear Modulus 26.5 GPa3.8 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33 · Compressive Strength 320 MPa46.4 ksi · Shear Strength 245 MPa35.5 ksi · Charpy V-Notch Impact (RT) 6 J4.4 ft·lbf

Physical

Density and transition temperatures.

Same in both: Density 2.81 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

105 W/m·K60.7 BTU/hr·ft·°F
150 W/m·K86.7 BTU/hr·ft·°F

Max Service Temperature (continuous)

100°C212 °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

26 % IACS
40 % IACS

Same in both: Electrical Resistivity 6.6×10⁻⁸ Ω·m2.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

40 / 100
55 / 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

65 / 100
70 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 70% · Weldability 25 / 100 · Formability (cold) 20 / 100 · Castability 35 / 100 · Brazeability / Solderability 15 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 215 MJ/kg92,433 BTU/lb · Embodied Carbon (primary production) 13 kg CO₂/kg · Embodied Water 1,250 L/kg150 gal/lb · Typical Recycled Content 5%

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 scale7A77

7A77 As Printed vs 7A77-T73 — frequently asked

Is 7A77-T73 stronger than 7A77 As Printed?

Yes. 7A77-T73 has a typical yield strength of 400 MPa (58 ksi) against 310 MPa (45 ksi) for 7A77 As Printed — about 29% more. Tensile strength is 470 MPa (68.2 ksi) vs 400 MPa (58 ksi).

Which condition does FabDigit quote by default, As Printed or T73?

As Printed is the default 7A77 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.

Which is easier to machine, 7A77 As Printed or 7A77-T73?

7A77-T73. Its machinability rates very good (70/100) against good (65/100) for 7A77 As Printed.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 7A77 As Printed and 7A77-T73 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.