Aluminum 2098-O vs 2098-T351
Aluminum · 2098 temper comparison
2098-O and 2098-T351 are two conditions of the same aluminum grade, 2098: O (annealed) versus T351 (T3, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. 2098-T351 is the stronger of the two: yield strength 290 MPa (42.1 ksi) against 140 MPa (20.3 ksi) for 2098-O, about 107% more; tensile strength follows at 400 MPa (58 ksi) vs 265 MPa (38.4 ksi). In exchange, 2098-O is the more ductile: elongation 17% versus 15% for 2098-T351, and 2098-T351 is harder (112 HB vs 70 HB). 2098-O runs hotter in service (150°C vs 120°C continuous) and 2098-O conducts heat better (120 W/m·K vs 92 W/m·K). On the shop floor, 2098-T351 machines more easily (50 vs 40 out of 100) and 2098-O welds better (fair vs poor).
2098-OChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
2098-T351Choose it when strength drives the design, or when the part is machined in volume.
2098-O vs 2098-T351: 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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 76 GPa11 Msi · Shear Modulus 29 GPa4.2 Msi · Bulk Modulus 74 GPa10.7 Msi · Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Same in both: Density 2.7 g/cm³0.1 lb/in³ · Melting Point (Solidus) 545°C1,013 °F · Liquidus Temperature 640°C1,184 °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 900 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 · 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) -0.7 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 10 / 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) 13.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 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.
2098-O vs 2098-T351 — frequently asked
Is 2098-T351 stronger than 2098-O?
Yes. 2098-T351 has a typical yield strength of 290 MPa (42.1 ksi) against 140 MPa (20.3 ksi) for 2098-O — about 107% more. Tensile strength is 400 MPa (58 ksi) vs 265 MPa (38.4 ksi).
Which condition does FabDigit quote by default, O or T351?
T851 is the default 2098 condition in the FabDigit quote flow (neither O nor T351). 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, 2098-O or 2098-T351?
2098-T351, by a small margin. Both rate fair for machinability — 50/100 against 40/100 for 2098-O; for welding the order is 2098-O first (fair, 35/100) then 2098-T351 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 2098-O and 2098-T351 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.