Materials / Compare
Plastic POM/Acetal vs. Plastic PPS GF40
Compare Plastic POM/Acetal vs. Plastic PPS GF40 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 | 69MPasourcetypical (single ASTM D638 tensile strength) | not given (tensile used) |
| Ultimate tensile strength | 69MPasourcetypical | 195MPasourcetensile strength, 5 mm/min |
| Compressive strength | 124MPasourcecompressive stress at 10% deformation | not sourced |
| Flexural strength | 99MPasourceflexural yield strength, typical | 285MPasourceflexural strength at break |
| Elongation at break | 75%sourcetypical | 1.9%sourcestrain at break, 5 mm/min |
| Young's modulus (stiffness) | 2.8GPasourcetypical | 14.7GPasourcetypical, 1 mm/min |
| Density | 1,420kg/m³sourcetypical (DuPont product information for Delrin 100 NC010; 'The data listed here fall within the normal range of product properties') | 1,650kg/m³sourcetypical |
| Strength to weight | 48.6kN·m/kg | 118kN·m/kg2.43x higher |
| Stiffness to weight | 1.97MN·m/kg | 8.91MN·m/kg4.52x higher |
| Poisson's ratio | 0.35sourcetypical | 0.35sourceglass-reinforced Fortron PPS (class value, not grade-specific) |
| Shear modulus | 1.04GPa | 5.44GPa5.25x stiffer in shear |
| Bulk modulus | 3.11GPa | 16.3GPa |
| Speed of sound | 1,404m/s | 2,985m/s |
| Thermal | ||
| Thermal conductivity | 0.4W/m·Ksourcetypical | 0.2W/m·Ksource40% glass-reinforced Fortron, 25 °C (not grade-specific) |
| Thermal expansion | 122µm/m·Ksourcemean, 29 to 60 °C | 12µm/m·Ksourceparallel (flow), mean -50 to 90 °C |
| 100 mm part over a 50 °C swing | 610µm growth | 60µm growth10.2x less |
| Specific heat | 1,465J/kg·Ksourceaverage -18 to 100 °C, Delrin acetal resins (not grade-specific) | not sourced |
| Heats up and cools (diffusivity) | 0.192mm²/s | not sourced |
| Thermal shock resistance | 52.5W/m | 144W/m2.74x more resistant |
| Melting point | 175°Csourcecrystalline melting point | 280°CsourceDSC, 10 °C/min |
| Glass transition | not sourced | 90°CsourceDSC, 10 °C/min |
| Max service temperature | 125°CsourceHDT 1.8 MPa (annealed) | 270°CsourceHDT 1.8 MPa |
| Values for | DuPont Delrin 100 acetal homopolymer, Table 2 'Typical Properties of Delrin Acetal Resins' (ASTM methods), Delrin Design Guide Module III hosted on delrin.com | Celanese Fortron 1140L4 (PPS, 40% glass fibre), injection moulding; FORTRON PPS Short-Term Properties Guide (PPS-012, 2016); thermal conductivity and Poisson for 40% glass-reinforced Fortron from the Fortron PPS Design Manual (PPS-050, 2013). |
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 POM/Acetal stronger than Plastic PPS GF40?
Plastic PPS GF40 is stronger: its tensile strength is 195 MPa against yield strength 69 MPa for Plastic POM/Acetal (2.83x).
Which is lighter, Plastic POM/Acetal or Plastic PPS GF40?
Plastic POM/Acetal is lighter: 1,420 kg/m³ against 1,650 kg/m³ for Plastic PPS GF40.
Which is stiffer, Plastic POM/Acetal or Plastic PPS GF40?
Plastic PPS GF40 is stiffer: Young's modulus 14.7 GPa against 2.8 GPa for Plastic POM/Acetal, so the same part in Plastic PPS GF40 deflects less under the same load.
Which is lighter for the same job, Plastic POM/Acetal or Plastic PPS GF40?
For the same stiffness or strength: Plastic PPS GF40 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 POM/Acetal | Plastic PPS GF40 |
|---|---|---|
| Stiff rod or tie (tension) | 4.52x heavier | lighter |
| Stiff beam (bending) | 1.97x heavier | lighter |
| Stiff panel or plate | 50% heavier | lighter |
| Strong rod or tie | 2.43x heavier | lighter |
| Strong beam | 1.72x heavier | lighter |
| Strong panel or plate | 45% 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 POM/Acetal or Plastic PPS GF40?
Plastic POM/Acetal conducts heat better: 0.4 W/m·K against 0.2 W/m·K for Plastic PPS GF40.
Which expands less with temperature?
Plastic PPS GF40 expands less: 12 µm/m·K against 122 µm/m·K for Plastic POM/Acetal.