Thermal conductivity against densityHigher and further left: spreads more heat for its weightThermal expansion against thermal conductivityLower and further right: warps less when heated
Try it on a partA bracket to run stress or thermal on, free in your browser
Victrex PEEK 450G (unreinforced, injection moulded), Victrex TDS rev. March 2026; Poisson from Victrex fluid-management flyer (2020-07)
Wood
Northern red oak (Quercus rubra), clear straight-grained specimens at 12% MC, parallel to grain unless stated; USDA FPL Wood Handbook FPL-GTR-282 (2021) Ch. 4 and Ch. 5
1
VICTREX PEEK 450G Technical Data SheetVictrexPlastic PEEK · Yield strength: typical, tensile yieldPlastic PEEK · Compressive strength: typical, 23 CPlastic PEEK · Flexural strength: typical, flexural stress at yield, 23 CPlastic PEEK · Elongation at break: typical, at breakPlastic PEEK · Young's modulus (stiffness): typical (nominal)Plastic PEEK · Density: typical (crystalline)Plastic PEEK · Thermal conductivity: typical, average, 23 CPlastic PEEK · Thermal expansion: average of flow/cross-flow, below Tg (<143 C)Plastic PEEK · Melting point: typical, DSCPlastic PEEK · Glass transition: onset (midpoint 150 C)Plastic PEEK · Max service temperature: UL 746B RTI, mechanical strength (continuous use index)
2
Wood Handbook (FPL-GTR-282), Chapter 5: Mechanical Properties of WoodUSDA Forest Products LaboratoryWood · Ultimate tensile strength: modulus of rupture (no direct tensile value)Wood · Compressive strength: compression parallel to grain (maximum crushing strength), 12% MCWood · Flexural strength: modulus of rupture (static bending), 12% MCWood · Young's modulus (stiffness): bending MOE, parallel to grainWood · Poisson's ratio: mu_LR (red oak group, ~12% MC)
3
Technical Note 218: Weights of Various Woods Grown in the United States (1953)USDA Forest Products LaboratoryWood · Density: average weight of clear wood at 8% and 15% moisture content
4
VICTREX PEEK for Use in Fluid Management (2020)VictrexPlastic PEEK · Poisson's ratio: typical
5
Wood Handbook (FPL-GTR-282), Chapter 4: Moisture Relations and Physical Properties of WoodUSDA Forest Products LaboratoryWood · Thermal conductivity: across grain, 12% MC (Table 4-7, approximate)Wood · Thermal expansion: parallel to grain, ovendry wood, range across speciesWood · Specific heat: solid wood (all species), 12% MC, 27 C
6
VICTREX PEEK 450G Technical Data Sheet (2012)Victrexarchived copyPlastic PEEK · Specific heat: typical, 23 °C, DSC (Victrex PEEK 450G TDS, revision Jul 2012)
Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Mechanical
Is Plastic PEEK stronger than Wood?
Wood is stronger: its tensile strength is 99 MPa against yield strength 98 MPa for Plastic PEEK (1%).
Which is lighter, Plastic PEEK or Wood?
Wood is lighter: 692 kg/m³ against 1,300 kg/m³ for Plastic PEEK.
Which is stiffer, Plastic PEEK or Wood?
Wood is stiffer: Young's modulus 12.5 GPa against 4 GPa for Plastic PEEK, so the same part in Wood deflects less under the same load.
Which is lighter for the same job, Plastic PEEK or Wood?
For the same stiffness or strength: Wood is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
Part that must be
Plastic PEEK
Wood
Stiff rod or tie (tension)
5.87x heavier
lighter
Stiff beam (bending)
3.32x heavier
lighter
Stiff panel or plate
2.75x heavier
lighter
Strong rod or tie
1.9x heavier
lighter
Strong beam
1.89x heavier
lighter
Strong panel or plate
1.89x 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).
Thermal
Which conducts heat better, Plastic PEEK or Wood?
Plastic PEEK conducts heat better: 0.29 W/m·K against 0.18 W/m·K for Wood.
Which expands less with temperature?
Wood expands less: 3.8 µm/m·K against 55 µm/m·K for Plastic PEEK.