Aluminum 7A77-HIP vs 7A77-T73
Aluminum · 7A77 temper comparison
7A77-HIP and 7A77-T73 are two conditions of the same aluminum grade, 7A77: HIP (hot isostatic pressed) 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 250 MPa (36.3 ksi) for 7A77-HIP, about 60% more; tensile strength follows at 470 MPa (68.2 ksi) vs 350 MPa (50.8 ksi). In exchange, 7A77-HIP is the more ductile: elongation 10% versus 8% for 7A77-T73, and 7A77-T73 is harder (135 HB vs 95 HB). 7A77-T73 runs hotter in service (150°C vs 100°C continuous) and 7A77-T73 conducts heat better (150 W/m·K vs 130 W/m·K).
7A77-HIPChoose it when the part is bent, formed or impact-loaded.
7A77-T73Choose it when strength drives the design, or when the part sees heat.
7A77-HIP vs 7A77-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
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
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
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
Max Service Temperature (continuous)
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
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
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
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.
7A77-HIP vs 7A77-T73 — frequently asked
Is 7A77-T73 stronger than 7A77-HIP?
Yes. 7A77-T73 has a typical yield strength of 400 MPa (58 ksi) against 250 MPa (36.3 ksi) for 7A77-HIP — about 60% more. Tensile strength is 470 MPa (68.2 ksi) vs 350 MPa (50.8 ksi).
Which condition does FabDigit quote by default, HIP or T73?
As Printed is the default 7A77 condition in the FabDigit quote flow (neither HIP nor T73). 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-HIP or 7A77-T73?
7A77-T73. Its machinability rates very good (70/100) against good (64/100) for 7A77-HIP.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 7A77-HIP 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.