Aluminum 1145 vs 1275
Aluminum · grade comparison
Aluminum 1145 and 1275 are both aluminum grades. 1145 is the stronger of the two: yield strength 150 MPa (21.8 ksi) against 90 MPa (13.1 ksi) for 1275, about 67% more; tensile strength follows at 165 MPa (23.9 ksi) vs 100 MPa (14.5 ksi). In exchange, 1275 is the more ductile: elongation 8% versus 4% for 1145, and 1145 is harder (42 HB vs 30 HB). 1275 runs hotter in service (120°C vs 100°C continuous). On the shop floor, 1145 sits in a lower cost tier (budget, $) than 1275 (premium, $$$).
1145Choose it when strength drives the design, or when cost is the deciding factor.
1275Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
1145 vs 1275: 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.
Bulk Modulus
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 · 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.
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Conductivity 230 W/m·K133 BTU/hr·ft·°F · 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
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)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 1,200 L/kg144 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 25.6 MN·m/kg · Thermal Diffusivity 94.7 mm²/s
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.
Manufacturing and finishing
| Capability | 1145 | 1275 |
|---|---|---|
| Sheet metal | Yes | — |
| Default condition | — | — |
| Relative cost | $ Budget | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Anodizing Type II | Yes | — |
| Cerakote | Yes | — |
| Chem Film (Alodine) | Yes | — |
| E-Coating | Yes | — |
| Electropolishing | Yes | — |
| Hard Anodize Type III w/ PTFE | Yes | — |
| Hard Anodizing Type III | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
| Powder Coating | Yes | — |
They share 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.
1145 vs 1275 — frequently asked
Is 1145 stronger than 1275?
Yes. 1145 has a typical yield strength of 150 MPa (21.8 ksi) against 90 MPa (13.1 ksi) for 1275 — about 67% more. Tensile strength is 165 MPa (23.9 ksi) vs 100 MPa (14.5 ksi).
Which is cheaper, 1145 or 1275?
1145 is the lower-cost material: it sits in the budget tier ($) while 1275 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
When should I choose 1145 over 1275?
Pick 1145 when strength drives the design, or when cost is the deciding factor. Pick 1275 when the part is bent, formed or impact-loaded, or when the part sees heat.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1145 and 1275 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.