Materials / Compare
Aluminum vs. Plastic TPU
Compare Aluminum vs. Plastic TPU 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 | 276MPasourcetypical, 0.2% offset, .500 in dia specimen | not given (tensile used) |
| Ultimate tensile strength | 310MPasourcetypical | 23.7MPasourcetypical, stress at break |
| Flexural strength | not sourced | 4.1MPasourcetypical |
| Elongation at break | 17%sourcetypical, in 4D, 0.500 in dia specimen | not sourced |
| Young's modulus (stiffness) | 68.3GPasourcetypical1,019x stiffer | 0.067GPasourcetypical |
| Density | 2,700kg/m³sourcenominal | 1,220kg/m³sourcetypical |
| Strength to weight | 102kN·m/kg5.26x higher | 19.4kN·m/kg |
| Stiffness to weight | 25.3MN·m/kg461x higher | 0.0549MN·m/kg |
| Poisson's ratio | 0.33sourcetypical (handbook physical constant) | not sourced |
| Shear modulus | 25.7GPa | not sourced |
| Bulk modulus | 67GPa | not sourced |
| Speed of sound | 5,030m/s | 234m/s |
| Thermal | ||
| Thermal conductivity | 167W/m·Ksourcetypical, 20 °C | not sourced |
| Thermal expansion | 23.6µm/m·Ksourcetypical, mean 20-100 °C | not sourced |
| 100 mm part over a 50 °C swing | 118µm growth | not sourced |
| Specific heat | 896J/kg·Ksourcetypical, at 100 °C | not sourced |
| Heats up and cools (diffusivity) | 69mm²/s | not sourced |
| Thermal shock resistance | 19,159W/m | not sourced |
| Melting point | 582–652°Csourcesolidus-liquidus | 217°Csourcetypical |
| Max service temperature | not sourced | 50.3°CsourceHDT 0.455 MPa (printed specimens) |
| Values for | 6061-T6/T651, Kaiser Aluminum typical properties (sheet, coil & plate datasheet); Poisson from MIL-HDBK-5J | Ultimaker TPU 95A, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS (file v5.00), April 29, 2022. |
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.
Plastic TPU is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Aluminum stronger than Plastic TPU?
Aluminum is stronger: its yield strength is 276 MPa against tensile strength 23.7 MPa for Plastic TPU (11.6x).
Which is lighter, Aluminum or Plastic TPU?
Plastic TPU is lighter: 1,220 kg/m³ against 2,700 kg/m³ for Aluminum.
Which is stiffer, Aluminum or Plastic TPU?
Aluminum is stiffer: Young's modulus 68.3 GPa against 0.067 GPa for Plastic TPU, so the same part in Aluminum deflects less under the same load.
Which is lighter for the same job, Aluminum or Plastic TPU?
For the same stiffness or strength: Aluminum 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 | Plastic TPU |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 461x heavier |
| Stiff beam (bending) | lighter | 14.4x heavier |
| Stiff panel or plate | lighter | 4.55x heavier |
| Strong rod or tie | lighter | 5.26x heavier |
| Strong beam | lighter | 2.32x heavier |
| Strong panel or plate | lighter | 1.54x 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).