Materials / Compare
Plastic TPU vs. Stainless Steel 303
Compare Plastic TPU vs. Stainless Steel 303 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) | 275MPasourceOutokumpu typical (product P = hot rolled plate, transverse) |
| Ultimate tensile strength | 23.7MPasourcetypical, stress at break | 585MPasourceOutokumpu typical |
| Flexural strength | 4.1MPasourcetypical | not sourced |
| Elongation at break | not sourced | 35%sourceOutokumpu typical, A5 |
| Young's modulus (stiffness) | 0.067GPasourcetypical | 200GPasourceat RT (Table 12) |
| Density | 1,220kg/m³sourcetypical | 7,900kg/m³sourceat RT |
| Strength to weight | 19.4kN·m/kg | 34.8kN·m/kg1.79x higher |
| Stiffness to weight | 0.0549MN·m/kg | 25.3MN·m/kg461x higher |
| Poisson's ratio | not sourced | 0.3sourcedesign value (structural stainless steels) |
| Shear modulus | not sourced | 76.9GPa |
| Bulk modulus | not sourced | 167GPa |
| Speed of sound | 234m/s | 5,032m/s |
| Thermal | ||
| Thermal conductivity | not sourced | 15W/m·Ksourceat RT |
| Thermal expansion | not sourced | 16µm/m·Ksourcemean, 20–100 °C |
| 100 mm part over a 50 °C swing | not sourced | 80µm growth |
| Specific heat | not sourced | 500J/kg·Ksourceat RT |
| Heats up and cools (diffusivity) | not sourced | 3.8mm²/s |
| Thermal shock resistance | not sourced | 902W/m |
| Melting point | 217°Csourcetypical | not sourced |
| Max service temperature | 50.3°CsourceHDT 0.455 MPa (printed specimens) | 871°Csourcecontinuous, scaling limit |
| 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. | 1.4305 / UNS S30300, Outokumpu typical values (hot rolled, solution annealed) from 'Steel Grades, Properties and Global Standards'; max service from Carpenter CarTech 303 datasheet |
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 303?
Stainless Steel 303 is stronger: its yield strength is 275 MPa against tensile strength 23.7 MPa for Plastic TPU (11.6x).
Which is lighter, Plastic TPU or Stainless Steel 303?
Plastic TPU is lighter: 1,220 kg/m³ against 7,900 kg/m³ for Stainless Steel 303.
Which is stiffer, Plastic TPU or Stainless Steel 303?
Stainless Steel 303 is stiffer: Young's modulus 200 GPa against 0.067 GPa for Plastic TPU, so the same part in Stainless Steel 303 deflects less under the same load.
Which is lighter for the same job, Plastic TPU or Stainless Steel 303?
For the same stiffness or strength: Plastic TPU is lighter for a strong beam, strong panel or plate; Stainless Steel 303 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 303 |
|---|---|---|
| Stiff rod or tie (tension) | 461x heavier | lighter |
| Stiff beam (bending) | 8.44x heavier | lighter |
| Stiff panel or plate | 2.22x heavier | lighter |
| Strong rod or tie | 1.79x heavier | lighter |
| Strong beam | lighter | 26% heavier |
| Strong panel or plate | lighter | 1.9x 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).