Aluminum 1275-H16 vs 1275-O
Aluminum · 1275 temper comparison
1275-H16 and 1275-O are two conditions of the same aluminum grade, 1275: H16 (strain hardened, three-quarter hard) versus O (annealed). The chemistry is identical, so every difference below comes from the condition. 1275-H16 is the stronger of the two: yield strength 105 MPa (15.2 ksi) against 25 MPa (3.63 ksi) for 1275-O, about 4.2 times as much; tensile strength follows at 115 MPa (16.7 ksi) vs 70 MPa (10.2 ksi). In exchange, 1275-O is the more ductile: elongation 42% versus 5% for 1275-H16, and 1275-H16 is harder (34 HB vs 19 HB). 1275-O runs hotter in service (150°C vs 120°C continuous). On the shop floor, 1275-H16 machines more easily (fair vs poor).
1275-H16Choose it when strength drives the design, or when the part is machined in volume.
1275-OChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
1275-H16 vs 1275-O: 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)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 69 GPa10 Msi · Shear Modulus 26 GPa3.8 Msi · Bulk Modulus 76 GPa11 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) 646°C1,195 °F · Liquidus Temperature 657°C1,215 °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) 23.6 µm/m·K13.1 µin/in·°F · Latent Heat of Fusion 397 J/g171 BTU/lb · Min Service Temperature -200°C-328 °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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 80 / 100 · Polishability 85 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 210 MJ/kg90,284 BTU/lb · Embodied Carbon (primary production) 13 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 3%
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.
1275-H16 vs 1275-O — frequently asked
Is 1275-H16 stronger than 1275-O?
Yes. 1275-H16 has a typical yield strength of 105 MPa (15.2 ksi) against 25 MPa (3.63 ksi) for 1275-O — about 4.2 times as much. Tensile strength is 115 MPa (16.7 ksi) vs 70 MPa (10.2 ksi).
Which condition does FabDigit quote by default, H16 or O?
H14 is the default 1275 condition in the FabDigit quote flow (neither H16 nor O). 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, 1275-H16 or 1275-O?
1275-H16. Its machinability rates fair (35/100) against poor (25/100) for 1275-O; for welding the order is 1275-O first (excellent, 95/100) then 1275-H16 (excellent, 90/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1275-H16 and 1275-O 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.