Materials / Compare
Plastic PTFE vs. Stainless 17-4PH
Compare Plastic PTFE vs. Stainless 17-4PH 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 | 9MPasourcetypical yield strength at 23 °C (Teflon PTFE, Table 8) | 1,275MPasourcetypical, transverse, sheet/strip |
| Ultimate tensile strength | 39.3MPasourcetypical, skived tape 0.13 mm | 1,379MPasourcetypical, transverse, sheet/strip |
| Elongation at break | 350%sourcetypical, skived tape 0.13 mm | 9%sourcetypical, transverse, in 2 in. (50.8 mm) |
| Young's modulus (stiffness) | not sourced | 197GPasourceH 900 |
| Density | 2,160kg/m³sourcetypical (standard specific gravity, ASTM D4894) | 7,800kg/m³sourceH 900 |
| Strength to weight | 4.17kN·m/kg | 163kN·m/kg39.2x higher |
| Stiffness to weight | not sourced | 25.3MN·m/kg |
| Poisson's ratio | 0.46sourcetypical, 23 °C (Teflon PTFE resins, Chemours handbook) | 0.272sourceH 900 (column) |
| Shear modulus | not sourced | 77.4GPa |
| Bulk modulus | not sourced | 144GPa |
| Speed of sound | not sourced | 5,026m/s |
| Thermal | ||
| Thermal conductivity | 0.25W/m·Ksourcetypical, granular resin, 4.6 mm specimen | 17.9W/m·Ksourceat 149 °C (300 °F), H 900 |
| Thermal expansion | 100µm/m·Ksourcetypical, granular resin, 23-60 °C (ASTM E228) | 10.8µm/m·Ksourcemean, 21–93 °C (70–200 °F), H 900 |
| 100 mm part over a 50 °C swing | 500µm growth | 54µm growth9.26x less |
| Specific heat | 1,400J/kg·Ksourcetypical, granular resin, 20 °C (ASTM D4591) | 460J/kg·Ksourcemean, 0–100 °C, H 900 |
| Heats up and cools (diffusivity) | 0.0827mm²/s | 4.99mm²/s60.3x faster |
| Thermal shock resistance | not sourced | 7,809W/m |
| Melting point | 327°Csourcesecond melting peak (sintered polymer), +/-10 | not sourced |
| Max service temperature | 260°Csourceservice temperature (Chemours general Teflon PTFE statement) | 316°Csourcestrength-retention limit (not oxidation) |
| Values for | Chemours Teflon PTFE 7C X granular molding resin, typical values (tensile/elongation measured on 0.13 mm skived tape) | Cleveland-Cliffs 17-4 PH, Condition H 900, sheet/strip, transverse (Product Data Bulletin, May 2021) |
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 Plastic PTFE stronger than Stainless 17-4PH?
Stainless 17-4PH is stronger: its yield strength is 1,275 MPa against 9 MPa for Plastic PTFE (142x).
Which is lighter, Plastic PTFE or Stainless 17-4PH?
Plastic PTFE is lighter: 2,160 kg/m³ against 7,800 kg/m³ for Stainless 17-4PH.
Which is lighter for the same job, Plastic PTFE or Stainless 17-4PH?
For the same stiffness or strength: Stainless 17-4PH is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PTFE | Stainless 17-4PH |
|---|---|---|
| Strong rod or tie | 39.2x heavier | lighter |
| Strong beam | 7.53x heavier | lighter |
| Strong panel or plate | 3.3x heavier | lighter |
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, Plastic PTFE or Stainless 17-4PH?
Stainless 17-4PH conducts heat better: 17.9 W/m·K against 0.25 W/m·K for Plastic PTFE.
Which expands less with temperature?
Stainless 17-4PH expands less: 10.8 µm/m·K against 100 µm/m·K for Plastic PTFE.