Materials / Compare
Aluminum 7075-T6 vs. Stainless 316
Compare Aluminum 7075-T6 vs. Stainless 316 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 | 503MPasourcetypical, 0.2% offset, .500 in dia specimen | 265MPasourcetypical (representative), annealed 1.0 mm sheet |
| Ultimate tensile strength | 572MPasourcetypical | 583MPasourcetypical (representative), annealed 1.0 mm sheet |
| Elongation at break | 11%sourcetypical, in 4D | 61%sourcetypical (representative), annealed, in 2 in. (51 mm) |
| Young's modulus (stiffness) | 71GPasourcetypical | 200GPasourcetypical, in tension |
| Density | 2,800kg/m³sourcenominal | 8,027kg/m³sourcetypical |
| Strength to weight | 180kN·m/kg5.44x higher | 33kN·m/kg |
| Stiffness to weight | 25.4MN·m/kg2% higher | 24.9MN·m/kg |
| Poisson's ratio | 0.33sourcetypical (handbook physical constant) | 0.3sourcedesign value (structural stainless steels) |
| Shear modulus | 26.7GPa | 76.9GPa2.88x stiffer in shear |
| Bulk modulus | 69.6GPa | 167GPa |
| Speed of sound | 5,036m/s | 4,992m/s |
| Thermal | ||
| Thermal conductivity | 130W/m·Ksourcetypical, 20 °C, T651 | 14.6W/m·Ksource20–100 °C |
| Thermal expansion | 23.4µm/m·Ksourcetypical, mean 20-100 °C | 16.5µm/m·Ksourcemean, 20–100 °C |
| 100 mm part over a 50 °C swing | 117µm growth | 82.5µm growth42% less |
| Specific heat | 960J/kg·Ksourcetypical, at 100 °C | 450J/kg·Ksourceat 20 °C |
| Heats up and cools (diffusivity) | 48.4mm²/s12x faster | 4.04mm²/s |
| Thermal shock resistance | 26,370W/m32.1x more resistant | 821W/m |
| Melting point | 532–635°Csourcemelting range | 1,390–1,440°Csourcemelting range |
| Max service temperature | not sourced | 871–899°Csourceoxidation (scaling) limit in air |
| Values for | 7075-T6/T651, Kaiser Aluminum rod & bar (mechanical) and sheet/coil/plate (physical) typical datasheets; Poisson from MIL-HDBK-5J | ATI 316 (UNS S31600), annealed 1.0 mm sheet, ATI technical data sheet (2012); Poisson's ratio from the Nickel Institute/SCI structural stainless design manual |
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 7075-T6 stronger than Stainless 316?
Aluminum 7075-T6 is stronger: its yield strength is 503 MPa against 265 MPa for Stainless 316 (1.9x).
Which is lighter, Aluminum 7075-T6 or Stainless 316?
Aluminum 7075-T6 is lighter: 2,800 kg/m³ against 8,027 kg/m³ for Stainless 316.
Which is stiffer, Aluminum 7075-T6 or Stainless 316?
Stainless 316 is stiffer: Young's modulus 200 GPa against 71 GPa for Aluminum 7075-T6, so the same part in Stainless 316 deflects less under the same load.
Which is lighter for the same job, Aluminum 7075-T6 or Stainless 316?
For the same stiffness or strength: Aluminum 7075-T6 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Aluminum 7075-T6 | Stainless 316 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 2% heavier |
| Stiff beam (bending) | lighter | 1.71x heavier |
| Stiff panel or plate | lighter | 2.03x heavier |
| Strong rod or tie | lighter | 5.44x heavier |
| Strong beam | lighter | 4.39x heavier |
| Strong panel or plate | lighter | 3.95x 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 7075-T6 or Stainless 316?
Aluminum 7075-T6 conducts heat better: 130 W/m·K against 14.6 W/m·K for Stainless 316.
Which expands less with temperature?
Stainless 316 expands less: 16.5 µm/m·K against 23.4 µm/m·K for Aluminum 7075-T6.