Materials / Compare
Plastic TPU vs. Stainless Steel 304
Compare Plastic TPU vs. Stainless Steel 304 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 | not given (tensile used) | 241MPasourcetypical, annealed, 70 °F (21 °C) |
| Ultimate tensile strength | 23.7MPasourcetypical, stress at break | 586MPasourcetypical, annealed, 70 °F (21 °C) |
| Flexural strength | 4.1MPasourcetypical | not sourced |
| Elongation at break | not sourced | 55%sourcetypical, annealed, in 2 in. (50.8 mm) |
| Young's modulus (stiffness) | 0.067GPasourcetypical | 193GPasourcetypical, in tension |
| Density | 1,220kg/m³sourcetypical6.58x lighter | 8,030kg/m³sourcetypical |
| Strength to weight | 19.4kN·m/kg | 30kN·m/kg1.54x higher |
| Stiffness to weight | 0.0549MN·m/kg | 24MN·m/kg438x higher |
| Poisson's ratio | not sourced | 0.3sourcedesign value (structural stainless steels) |
| Shear modulus | not sourced | 74.2GPa |
| Bulk modulus | not sourced | 161GPa |
| Speed of sound | 234m/s | 4,903m/s |
| Thermal | ||
| Thermal conductivity | not sourced | 16.2W/m·Ksourceat 100 °C |
| Thermal expansion | not sourced | 16.9µm/m·Ksourcemean, 0–100 °C |
| 100 mm part over a 50 °C swing | not sourced | 84.5µm growth |
| Specific heat | not sourced | 500J/kg·Ksourcemean, 0–100 °C |
| Heats up and cools (diffusivity) | not sourced | 4.03mm²/s |
| Thermal shock resistance | not sourced | 838W/m |
| Melting point | 217°Csourcetypical | 1,399–1,454°Csourcemelting range |
| Max service temperature | 50.3°CsourceHDT 0.455 MPa (printed specimens) | 899°Csourcecontinuous, oxidation (scaling) limit in air |
| Values for | 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. | Type 304, annealed flat-rolled (Cleveland-Cliffs 304/304L Product Data Bulletin, May 2021); 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.
Plastic TPU is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Plastic TPU stronger than Stainless Steel 304?
Stainless Steel 304 is stronger: its yield strength is 241 MPa against tensile strength 23.7 MPa for Plastic TPU (10.2x).
Which is lighter, Plastic TPU or Stainless Steel 304?
Plastic TPU is lighter: 1,220 kg/m³ against 8,030 kg/m³ for Stainless Steel 304.
Which is stiffer, Plastic TPU or Stainless Steel 304?
Stainless Steel 304 is stiffer: Young's modulus 193 GPa against 0.067 GPa for Plastic TPU, so the same part in Stainless Steel 304 deflects less under the same load.
Which is lighter for the same job, Plastic TPU or Stainless Steel 304?
For the same stiffness or strength: Plastic TPU is lighter for a strong beam, strong panel or plate; Stainless Steel 304 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie.
| Part that must be | Plastic TPU | Stainless Steel 304 |
|---|---|---|
| Stiff rod or tie (tension) | 438x heavier | lighter |
| Stiff beam (bending) | 8.15x heavier | lighter |
| Stiff panel or plate | 2.16x heavier | lighter |
| Strong rod or tie | 1.54x heavier | lighter |
| Strong beam | lighter | 40% heavier |
| Strong panel or plate | lighter | 2.06x 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).