Materials / Compare
Nickel Inconel 718 vs. Plastic PTFE
Compare Nickel Inconel 718 vs. Plastic PTFE 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 | 1,207MPasourcetypical, 1.0 in. hot-rolled bar, 0.2% offset | 9MPasourcetypical yield strength at 23 °C (Teflon PTFE, Table 8) |
| Ultimate tensile strength | 1,389MPasourcetypical, 1.0 in. bar | 39.3MPasourcetypical, skived tape 0.13 mm |
| Elongation at break | 20%sourcetypical, 1.0 in. bar | 350%sourcetypical, skived tape 0.13 mm |
| Young's modulus (stiffness) | 200GPasourcetypical, 21 °C, annealed + aged | not sourced |
| Density | 8,221kg/m³sourcenominal, annealed and aged | 2,160kg/m³sourcetypical (standard specific gravity, ASTM D4894) |
| Strength to weight | 147kN·m/kg35.2x higher | 4.17kN·m/kg |
| Stiffness to weight | 24.3MN·m/kg | not sourced |
| Poisson's ratio | 0.294sourcetypical, 21 °C, annealed + aged | 0.46sourcetypical, 23 °C (Teflon PTFE resins, Chemours handbook) |
| Shear modulus | 77.3GPa | not sourced |
| Bulk modulus | 162GPa | not sourced |
| Speed of sound | 4,932m/s | not sourced |
| Thermal | ||
| Thermal conductivity | 11.4W/m·Ksourcetypical, 21 °C, annealed + aged (calculated from resistivity per footnote a) | 0.25W/m·Ksourcetypical, granular resin, 4.6 mm specimen |
| Thermal expansion | 13.2µm/m·Ksourcetypical, mean 21-93 °C, annealed + aged | 100µm/m·Ksourcetypical, granular resin, 23-60 °C (ASTM E228) |
| 100 mm part over a 50 °C swing | 66µm growth7.58x less | 500µm growth |
| Specific heat | 435J/kg·Ksourcetypical, 21 °C | 1,400J/kg·Ksourcetypical, granular resin, 20 °C (ASTM D4591) |
| Heats up and cools (diffusivity) | 3.19mm²/s38.6x faster | 0.0827mm²/s |
| Thermal shock resistance | 3,680W/m | not sourced |
| Melting point | 1,260–1,336°Csourcemelting range | 327°Csourcesecond melting peak (sintered polymer), +/-10 |
| Max service temperature | 704°Csourceupper use temperature stated by producer | 260°Csourceservice temperature (Chemours general Teflon PTFE statement) |
| Values for | INCONEL alloy 718, standard grade, 1750 °F/1 hr anneal + 1325 °F/8 hr F.C. to 1150 °F aged; Special Metals bulletin SMC-045 typical values | Chemours Teflon PTFE 7C X granular molding resin, typical values (tensile/elongation measured on 0.13 mm skived tape) |
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 Nickel Inconel 718 stronger than Plastic PTFE?
Nickel Inconel 718 is stronger: its yield strength is 1,207 MPa against 9 MPa for Plastic PTFE (134x).
Which is lighter, Nickel Inconel 718 or Plastic PTFE?
Plastic PTFE is lighter: 2,160 kg/m³ against 8,221 kg/m³ for Nickel Inconel 718.
Which is lighter for the same job, Nickel Inconel 718 or Plastic PTFE?
For the same stiffness or strength: Nickel Inconel 718 is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Nickel Inconel 718 | Plastic PTFE |
|---|---|---|
| Strong rod or tie | lighter | 35.2x heavier |
| Strong beam | lighter | 6.88x heavier |
| Strong panel or plate | lighter | 3.04x 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, Nickel Inconel 718 or Plastic PTFE?
Nickel Inconel 718 conducts heat better: 11.4 W/m·K against 0.25 W/m·K for Plastic PTFE.
Which expands less with temperature?
Nickel Inconel 718 expands less: 13.2 µm/m·K against 100 µm/m·K for Plastic PTFE.