Aluminum 2618-T61 vs 2618-T6511
Aluminum · 2618 temper comparison
2618-T61 and 2618-T6511 are two conditions of the same aluminum grade, 2618: T61 (T6 variant, underaged) versus T6511 (T6, stress relieved by stretching, minor straightening). The chemistry is identical, so every difference below comes from the condition. Both yield at about 372 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (T6 variant, underaged versus T6, stress relieved by stretching, minor straightening). 2618-T61 is the more ductile: elongation 10% versus 8% for 2618-T6511, and 2618-T6511 is harder (74 HRB vs 70 HRB).
2618-T61Choose it when the part is bent, formed or impact-loaded.
2618-T61 vs 2618-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
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 74.5 GPa10.8 Msi · Shear Modulus 28 GPa4.1 Msi · Bulk Modulus 76 GPa11 Msi · Poisson's Ratio 0.33 · Fatigue Strength (Endurance Limit) 125 MPa18.1 ksi
Physical
Density and transition temperatures.
Same in both: Density 2.76 g/cm³0.1 lb/in³ · Melting Point (Solidus) 549°C1,020 °F · Liquidus Temperature 638°C1,180 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 146 W/m·K84.4 BTU/hr·ft·°F · 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 389 J/g167 BTU/lb · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 37 % IACS · Electrical Resistivity 4.66×10⁻⁸ Ω·m1.83 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.7 V · Corrosion Resistance 32 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 22 / 100 · Castability 20 / 100 · Brazeability / Solderability 15 / 100 · Polishability 55 / 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 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.
2618-T61 vs 2618-T6511 — frequently asked
What is the difference between 2618-T61 and 2618-T6511?
2618-T61 and 2618-T6511 are two conditions of the same aluminum grade, 2618: T61 (T6 variant, underaged) versus T6511 (T6, stress relieved by stretching, minor straightening). The chemistry is identical, so every difference below comes from the condition. Both yield at about 372 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (T6 variant, underaged versus T6, stress relieved by stretching, minor straightening).
Which condition does FabDigit quote by default, T61 or T6511?
Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.
When should I choose 2618-T61 over 2618-T6511?
Pick 2618-T61 when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 2618-T61 and 2618-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.