Materials / Compare
Aluminum 7050-T7451 vs. Steel AISI 1018
Compare Aluminum 7050-T7451 vs. Steel AISI 1018 strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 469MPasourcetypical, longitudinal, 0.2% offset | 372MPasourceproducer-stated, cold drawn |
| Ultimate tensile strength | 524MPasourcetypical, longitudinal | 441MPasourceproducer-stated, cold drawn |
| Elongation at break | 11%sourcetypical, longitudinal | 15%sourcein 2 in (50.8 mm) |
| Young's modulus (stiffness) | 70.3GPasourcetypical | 200GPasourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Density | 2,830kg/m³sourcenominal | 7,861kg/m³sourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Strength to weight | 166kN·m/kg3.5x higher | 47.3kN·m/kg |
| Stiffness to weight | 24.8MN·m/kg | 25.4MN·m/kg2% higher |
| Poisson's ratio | 0.33sourcetypical (handbook physical constant) | 0.32sourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Shear modulus | 26.4GPa | 75.7GPa2.87x stiffer in shear |
| Bulk modulus | 68.9GPa | 185GPa |
| Speed of sound | 4,984m/s | 5,043m/s |
| Thermal | ||
| Thermal conductivity | 157W/m·Ksourcetypical, 20 °C | 51.9W/m·Ksourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Thermal expansion | 23.5µm/m·Ksourcetypical, mean 20-100 °C | 12µm/m·Ksourcebase material: unalloyed carbon steel, Ovako family table (S275JR, 'none alloyed structural steels', C <= 0.21%); mean 20-300 °C |
| 100 mm part over a 50 °C swing | 118µm growth | 60µm growth1.96x less |
| Specific heat | 860J/kg·Ksourcetypical, at 100 °C | 486J/kg·Ksourcebase material: AISI 1025 plain carbon steel (MIL-HDBK-5J design value; ASTM A108 bar is the cold-finished carbon-steel bar spec that also covers 1018) |
| Heats up and cools (diffusivity) | 64.5mm²/s4.75x faster | 13.6mm²/s |
| Thermal shock resistance | 29,862W/m5.46x more resistant | 5,473W/m |
| Melting point | 524–635°Csourcemelting range | not sourced |
| Values for | 7050-T7451 plate, Kaiser Aluminum sheet, coil & plate typical datasheet (longitudinal); Poisson from MIL-HDBK-5J | AISI 1018 cold drawn bar (Niagara LaSalle, cold-finished bar producer) |
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Is Aluminum 7050-T7451 stronger than Steel AISI 1018?
Aluminum 7050-T7451 is stronger: its yield strength is 469 MPa against 372 MPa for Steel AISI 1018 (26%).
Which is lighter, Aluminum 7050-T7451 or Steel AISI 1018?
Aluminum 7050-T7451 is lighter: 2,830 kg/m³ against 7,861 kg/m³ for Steel AISI 1018.
Which is stiffer, Aluminum 7050-T7451 or Steel AISI 1018?
Steel AISI 1018 is stiffer: Young's modulus 200 GPa against 70.3 GPa for Aluminum 7050-T7451, so the same part in Steel AISI 1018 deflects less under the same load.
Which is lighter for the same job, Aluminum 7050-T7451 or Steel AISI 1018?
For the same stiffness or strength: Aluminum 7050-T7451 is lighter for a stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate; Steel AISI 1018 is lighter for a stiff rod or tie (tension).
| Part that must be | Aluminum 7050-T7451 | Steel AISI 1018 |
|---|---|---|
| Stiff rod or tie (tension) | 2% heavier | lighter |
| Stiff beam (bending) | lighter | 1.65x heavier |
| Stiff panel or plate | lighter | 1.96x heavier |
| Strong rod or tie | lighter | 3.5x heavier |
| Strong beam | lighter | 3.24x heavier |
| Strong panel or plate | lighter | 3.12x heavier |
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Aluminum 7050-T7451 or Steel AISI 1018?
Aluminum 7050-T7451 conducts heat better: 157 W/m·K against 51.9 W/m·K for Steel AISI 1018.
Which expands less with temperature?
Steel AISI 1018 expands less: 12 µm/m·K against 23.5 µm/m·K for Aluminum 7050-T7451.