Materials / Compare
Plastic PEEK vs. Titanium
Compare Plastic PEEK vs. Titanium 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 | 98MPasourcetypical, tensile yield | 885MPasourcetypical, plate (>0.187 in), annealed, 0.2% offset |
| Ultimate tensile strength | not sourced | 940MPasourcetypical, plate, annealed |
| Compressive strength | 125MPasourcetypical, 23 C | not sourced |
| Flexural strength | 165MPasourcetypical, flexural stress at yield, 23 C | not sourced |
| Elongation at break | 25%sourcetypical, at break | 16%sourcetypical, in 2 in., plate annealed |
| Young's modulus (stiffness) | 4GPasourcetypical (nominal) | 107–122GPasourcetypical range, 20 °C |
| Density | 1,300kg/m³sourcetypical (crystalline) | 4,430kg/m³sourcenominal |
| Strength to weight | 75.4kN·m/kg | 200kN·m/kg2.65x higher |
| Stiffness to weight | 3.08MN·m/kg | 25.8MN·m/kg8.4x higher |
| Poisson's ratio | 0.38sourcetypical | 0.342sourcemean of TIMET measurements |
| Shear modulus | 1.45GPa | 42.7GPa29.4x stiffer in shear |
| Bulk modulus | 5.56GPa | 121GPa |
| Speed of sound | 1,754m/s | 5,084m/s |
| Thermal | ||
| Thermal conductivity | 0.29W/m·Ksourcetypical, average, 23 C | 6.6W/m·Ksourcetypical, 20 °C, mill annealed |
| Thermal expansion | 55µm/m·Ksourceaverage of flow/cross-flow, below Tg (<143 C) | 9µm/m·Ksourcetypical, mean 0-100 °C |
| 100 mm part over a 50 °C swing | 275µm growth | 45µm growth6.11x less |
| Specific heat | 2,200J/kg·Ksourcetypical, 23 °C, DSC (Victrex PEEK 450G TDS, revision Jul 2012) | 580J/kg·Ksourcetypical, 20 °C |
| Heats up and cools (diffusivity) | 0.101mm²/s | 2.57mm²/s25.3x faster |
| Thermal shock resistance | 80.1W/m | 3,730W/m46.6x more resistant |
| Melting point | 343°Csourcetypical, DSC | 1,630–1,650°Csourcemelting range |
| Glass transition | 143°Csourceonset (midpoint 150 C) | not sourced |
| Max service temperature | 240°CsourceUL 746B RTI, mechanical strength (continuous use index) | 400°Csourceupper recommended use temperature |
| Values for | Victrex PEEK 450G (unreinforced, injection moulded), Victrex TDS rev. March 2026; Poisson from Victrex fluid-management flyer (2020-07) | TIMETAL 6-4 (Ti-6Al-4V Grade 5) annealed plate typical (TIMET properties manual) + TIMET datasheet TMC-0150 physical properties |
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 PEEK stronger than Titanium?
Titanium is stronger: its yield strength is 885 MPa against 98 MPa for Plastic PEEK (9.03x).
Which is lighter, Plastic PEEK or Titanium?
Plastic PEEK is lighter: 1,300 kg/m³ against 4,430 kg/m³ for Titanium.
Which is stiffer, Plastic PEEK or Titanium?
Titanium is stiffer: Young's modulus 115 GPa against 4 GPa for Plastic PEEK, so the same part in Titanium deflects less under the same load.
Which is lighter for the same job, Plastic PEEK or Titanium?
For the same stiffness or strength: Plastic PEEK is lighter for a stiff panel or plate, strong panel or plate; Titanium is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie, strong beam.
| Part that must be | Plastic PEEK | Titanium |
|---|---|---|
| Stiff rod or tie (tension) | 8.4x heavier | lighter |
| Stiff beam (bending) | 1.57x heavier | lighter |
| Stiff panel or plate | lighter | 11% heavier |
| Strong rod or tie | 2.65x heavier | lighter |
| Strong beam | 27% heavier | lighter |
| Strong panel or plate | lighter | 13% 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, Plastic PEEK or Titanium?
Titanium conducts heat better: 6.6 W/m·K against 0.29 W/m·K for Plastic PEEK.
Which expands less with temperature?
Titanium expands less: 9 µm/m·K against 55 µm/m·K for Plastic PEEK.