Aluminum 2618A-O vs 2618A-T6511
Aluminum · 2618A temper comparison
2618A-O and 2618A-T6511 are two conditions of the same aluminum grade, 2618A: O (annealed) versus T6511 (T6, stress relieved by stretching, minor straightening). The chemistry is identical, so every difference below comes from the condition. 2618A-T6511 is the stronger of the two: yield strength 370 MPa (53.7 ksi) against 130 MPa (18.9 ksi) for 2618A-O, about 185% more; tensile strength follows at 435 MPa (63.1 ksi) vs 240 MPa (34.8 ksi). In exchange, 2618A-O is the more ductile: elongation 18% versus 8% for 2618A-T6511, and 2618A-T6511 is harder (115 HB vs 65 HB). 2618A-O conducts electricity better (44 % IACS vs 39 % IACS). On the shop floor, 2618A-T6511 machines more easily (good vs fair).
2618A-OChoose it when the part is bent, formed or impact-loaded.
2618A-T6511Choose it when strength drives the design, or when the part is machined in volume.
2618A-O vs 2618A-T6511: 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
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 74 GPa10.7 Msi · Shear Modulus 27.5 GPa4 Msi · Bulk Modulus 72 GPa10.4 Msi · Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Same in both: Density 2.76 g/cm³0.1 lb/in³ · Melting Point (Solidus) 502°C936 °F · Liquidus Temperature 638°C1,180 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Same in both: Specific Heat Capacity 875 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 22.3 µm/m·K12.4 µin/in·°F · Latent Heat of Fusion 390 J/g168 BTU/lb · Max Service Temperature (continuous) 200°C392 °F · 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) -0.72 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 15 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 210 MJ/kg90,284 BTU/lb · Embodied Carbon (primary production) 14 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 12%
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.
2618A-O vs 2618A-T6511 — frequently asked
Is 2618A-T6511 stronger than 2618A-O?
Yes. 2618A-T6511 has a typical yield strength of 370 MPa (53.7 ksi) against 130 MPa (18.9 ksi) for 2618A-O — about 185% more. Tensile strength is 435 MPa (63.1 ksi) vs 240 MPa (34.8 ksi).
Which condition does FabDigit quote by default, O or T6511?
T851 is the default 2618A condition in the FabDigit quote flow (neither O nor T6511). 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, 2618A-O or 2618A-T6511?
2618A-T6511. Its machinability rates good (68/100) against fair (45/100) for 2618A-O.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 2618A-O and 2618A-T6511 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.