Materials / Compare
FDM PAHT-CF vs. Steel AISI 4340
Compare FDM PAHT-CF 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 | 92MPasourcetypical | 1,140MPasourcetypical, transverse |
| Flexural strength | 125MPasourcetypical | not sourced |
| Elongation at break | 8.4%sourcetypical | 18%sourcetypical, transverse |
| Young's modulus (stiffness) | 3.86GPasourcetypical | 200GPasourceMIL-HDBK-5J design value (AISI 4340, quenched and tempered) |
| Density | 1,060kg/m³sourcetypical7.4x lighter | 7,840kg/m³sourcetypical |
| Strength to weight | 86.8kN·m/kg | 132kN·m/kg1.52x higher |
| Stiffness to weight | 3.64MN·m/kg | 25.5MN·m/kg7x higher |
| Poisson's ratio | not sourced | 0.32sourceMIL-HDBK-5J design value (AISI 4340, quenched and tempered) |
| Shear modulus | not sourced | 75.7GPa |
| Bulk modulus | not sourced | 185GPa |
| Speed of sound | 1,908m/s | 5,049m/s |
| Thermal | ||
| Thermal conductivity | not sourced | 37.5W/m·Ksourcetypical |
| Thermal expansion | not sourced | 11.3µm/m·Ksourcemean, -18 to 93 °C |
| 100 mm part over a 50 °C swing | not sourced | 56.5µm growth |
| Specific heat | not sourced | 448J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | not sourced | 10.7mm²/s |
| Thermal shock resistance | not sourced | 11,678W/m |
| Melting point | 225°Csourcetypical | not sourced |
| Glass transition | 70°Csourcetypical | not sourced |
| Max service temperature | 170°CsourceHDT 1.8 MPa | not sourced |
| Values for | Bambu Lab PAHT-CF, TDS V3.0, printed specimens X-Y, dry state; nozzle 290 °C, bed 100 °C, 100 mm/s, 100% infill; annealed and dried 80 °C for 12 h before testing. | 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.
FDM PAHT-CF is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is FDM PAHT-CF stronger than Steel AISI 4340?
Steel AISI 4340 is stronger: its yield strength is 1,035 MPa against tensile strength 92 MPa for FDM PAHT-CF (11.3x).
Which is lighter, FDM PAHT-CF or Steel AISI 4340?
FDM PAHT-CF is lighter: 1,060 kg/m³ against 7,840 kg/m³ for Steel AISI 4340.
Which is stiffer, FDM PAHT-CF or Steel AISI 4340?
Steel AISI 4340 is stiffer: Young's modulus 200 GPa against 3.86 GPa for FDM PAHT-CF, so the same part in Steel AISI 4340 deflects less under the same load.
Which is lighter for the same job, FDM PAHT-CF or Steel AISI 4340?
For the same stiffness or strength: FDM PAHT-CF 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 | FDM PAHT-CF | Steel AISI 4340 |
|---|---|---|
| Stiff rod or tie (tension) | 7x heavier | lighter |
| Stiff beam (bending) | lighter | 3% heavier |
| Stiff panel or plate | lighter | 1.98x heavier |
| Strong rod or tie | 1.52x heavier | lighter |
| Strong beam | lighter | 47% heavier |
| Strong panel or plate | lighter | 2.21x 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).