Materials / Compare
Plastic PPS GF40 vs. Steel AISI 4340
Compare Plastic PPS GF40 vs. Steel AISI 4340 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 | not given (tensile used) | 1,035MPasourcetypical, transverse |
| Ultimate tensile strength | 195MPasourcetensile strength, 5 mm/min | 1,140MPasourcetypical, transverse |
| Flexural strength | 285MPasourceflexural strength at break | not sourced |
| Elongation at break | 1.9%sourcestrain at break, 5 mm/min | 18%sourcetypical, transverse |
| Young's modulus (stiffness) | 14.7GPasourcetypical, 1 mm/min | 200GPasourceMIL-HDBK-5J design value (AISI 4340, quenched and tempered) |
| Density | 1,650kg/m³sourcetypical4.75x lighter | 7,840kg/m³sourcetypical |
| Strength to weight | 118kN·m/kg | 132kN·m/kg12% higher |
| Stiffness to weight | 8.91MN·m/kg | 25.5MN·m/kg2.86x higher |
| Poisson's ratio | 0.35sourceglass-reinforced Fortron PPS (class value, not grade-specific) | 0.32sourceMIL-HDBK-5J design value (AISI 4340, quenched and tempered) |
| Shear modulus | 5.44GPa | 75.7GPa13.9x stiffer in shear |
| Bulk modulus | 16.3GPa | 185GPa |
| Speed of sound | 2,985m/s | 5,049m/s |
| Thermal | ||
| Thermal conductivity | 0.2W/m·Ksource40% glass-reinforced Fortron, 25 °C (not grade-specific) | 37.5W/m·Ksourcetypical |
| Thermal expansion | 12µm/m·Ksourceparallel (flow), mean -50 to 90 °C | 11.3µm/m·Ksourcemean, -18 to 93 °C |
| 100 mm part over a 50 °C swing | 60µm growth | 56.5µm growth6% less |
| Specific heat | not sourced | 448J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | not sourced | 10.7mm²/s |
| Thermal shock resistance | 144W/m | 11,678W/m81.3x more resistant |
| Melting point | 280°CsourceDSC, 10 °C/min | not sourced |
| Glass transition | 90°CsourceDSC, 10 °C/min | not sourced |
| Max service temperature | 270°CsourceHDT 1.8 MPa | not sourced |
| Values for | 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). | Carpenter (Latrobe) Lescalloy 4340 VAC-ARC datasheet; mechanical row for 1100 °F temper; physical properties grade-level |
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 PPS GF40 stronger than Steel AISI 4340?
Steel AISI 4340 is stronger: its yield strength is 1,035 MPa against tensile strength 195 MPa for Plastic PPS GF40 (5.31x).
Which is lighter, Plastic PPS GF40 or Steel AISI 4340?
Plastic PPS GF40 is lighter: 1,650 kg/m³ against 7,840 kg/m³ for Steel AISI 4340.
Which is stiffer, Plastic PPS GF40 or Steel AISI 4340?
Steel AISI 4340 is stiffer: Young's modulus 200 GPa against 14.7 GPa for Plastic PPS GF40, so the same part in Steel AISI 4340 deflects less under the same load.
Which is lighter for the same job, Plastic PPS GF40 or Steel AISI 4340?
For the same stiffness or strength: Plastic PPS GF40 is lighter for a stiff beam (bending), stiff panel or plate, strong beam, strong panel or plate; Steel AISI 4340 is lighter for a stiff rod or tie (tension), strong rod or tie.
| Part that must be | Plastic PPS GF40 | Steel AISI 4340 |
|---|---|---|
| Stiff rod or tie (tension) | 2.86x heavier | lighter |
| Stiff beam (bending) | lighter | 29% heavier |
| Stiff panel or plate | lighter | 1.99x heavier |
| Strong rod or tie | 12% heavier | lighter |
| Strong beam | lighter | 1.56x heavier |
| Strong panel or plate | lighter | 2.06x 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 PPS GF40 or Steel AISI 4340?
Steel AISI 4340 conducts heat better: 37.5 W/m·K against 0.2 W/m·K for Plastic PPS GF40.
Which expands less with temperature?
Steel AISI 4340 expands less: 11.3 µm/m·K against 12 µm/m·K for Plastic PPS GF40.
Among 72 materials
Related comparisons
- Plastic PPS GF40 vs. Plastic PBT GF30
- Plastic PPS GF40 vs. Plastic LCP GF30
- Plastic PPS GF40 vs. Concrete
- Plastic PPS GF40 vs. PCB Laminate FR-4
- Steel AISI 4340 vs. Nickel Inconel 718
- Steel AISI 4340 vs. DMLS 17-4PH Stainless Steel
- Steel AISI 4340 vs. Stainless Steel 17-4PH
- Steel AISI 4340 vs. Steel AISI 1045