Aluminum 7129-T6 vs 7129-T73
Aluminum · 7129 temper comparison
7129-T6 and 7129-T73 are two conditions of the same aluminum grade, 7129: T6 (solution heat treated and artificially aged) versus T73 (solution heat treated and overaged for stress-corrosion resistance). The chemistry is identical, so every difference below comes from the condition. 7129-T6 is the stronger of the two: yield strength 350 MPa (50.8 ksi) against 290 MPa (42.1 ksi) for 7129-T73, about 21% more; tensile strength follows at 400 MPa (58 ksi) vs 345 MPa (50 ksi). In exchange, 7129-T73 is the more ductile: elongation 13% versus 11% for 7129-T6, and 7129-T6 is harder (120 HB vs 105 HB). 7129-T73 runs hotter in service (150°C vs 120°C continuous) and 7129-T73 conducts electricity better (39 % IACS vs 32 % IACS).
7129-T6Choose it when strength drives the design.
7129-T73Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
7129-T6 vs 7129-T73: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 70 GPa10.2 Msi · Shear Modulus 26.5 GPa3.8 Msi · Bulk Modulus 70 GPa10.2 Msi · Poisson's Ratio 0.33 · Compressive Strength 355 MPa51.5 ksi · Hardness, Vickers 130 HV
Physical
Density and transition temperatures.
Same in both: Density 2.8 g/cm³0.1 lb/in³ · Melting Point (Solidus) 480°C896 °F · Liquidus Temperature 635°C1,175 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 865 J/kg·K0.21 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
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.84 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 70% · Weldability 30 / 100 · Formability (cold) 35 / 100 · Brazeability / Solderability 15 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 205 MJ/kg88,134 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,150 L/kg138 gal/lb · Typical Recycled Content 25%
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.
7129-T6 vs 7129-T73 — frequently asked
Is 7129-T6 stronger than 7129-T73?
Yes. 7129-T6 has a typical yield strength of 350 MPa (50.8 ksi) against 290 MPa (42.1 ksi) for 7129-T73 — about 21% more. Tensile strength is 400 MPa (58 ksi) vs 345 MPa (50 ksi).
Which condition does FabDigit quote by default, T6 or T73?
T6 is the default 7129 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 7129-T6 over 7129-T73?
Pick 7129-T6 when strength drives the design. Pick 7129-T73 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 7129-T6 and 7129-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.