Materials / Compare
FDM Polycarbonate vs. Steel
Compare FDM Polycarbonate vs. Steel 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 | 53.3MPasourcetypical | 385MPasourcetypical: mean of 20,295 A992 flange mill-test coupons (1998 SSPC survey), as reported by AISC |
| Ultimate tensile strength | 53.3MPasourcetypical, peak stress (= stress at yield) | 505MPasourcetypical: mean of 20,295 A992 flange mill-test coupons (1998 SSPC survey) |
| Flexural strength | 89.4MPasourcetypical | not sourced |
| Elongation at break | 9.2%sourcetypical | not sourced |
| Young's modulus (stiffness) | 2.39GPasourcetypical | 200GPasourcedesign value (AISC 360-16) |
| Density | 1,180–1,200kg/m³sourcerange | 7,850kg/m³sourcenominal (constructional data) |
| Strength to weight | 44.8kN·m/kg | 49kN·m/kg9% higher |
| Stiffness to weight | 2.01MN·m/kg | 25.5MN·m/kg12.7x higher |
| Poisson's ratio | 0.38sourcebase material: polycarbonate family typical (Covestro Part and Mold Design guide, Table 3-1) | 0.3sourcedesign value (AISC 360-16 Commentary) |
| Shear modulus | 0.867GPa | 76.9GPa88.7x stiffer in shear |
| Bulk modulus | 3.33GPa | 167GPa |
| Speed of sound | 1,418m/s | 5,048m/s |
| Thermal | ||
| Thermal conductivity | 0.2W/m·Ksourcebase material: Covestro Makrolon 2405 injection-molding PC, typical, through-plane, 23 °C | 48W/m·Ksourcenominal at 20 °C |
| Thermal expansion | 65µm/m·Ksourcebase material: Covestro Makrolon 2405 injection-molding PC, typical, 23-55 °C, parallel | 12µm/m·Ksourcenominal (constructional data, no temperature range stated) |
| 100 mm part over a 50 °C swing | 325µm growth | 60µm growth5.42x less |
| Specific heat | not sourced | 460–480J/kg·Ksourcebase material: EN S275JR unalloyed structural steel (the EN counterpart of A36), typical, 50/100 °C |
| Heats up and cools (diffusivity) | not sourced | 13mm²/s |
| Thermal shock resistance | 42.5W/m | 5,390W/m127x more resistant |
| Glass transition | 108°Csourcetypical | not sourced |
| Max service temperature | 105°CsourceHDT 0.455 MPa (printed specimens) | not sourced |
| Values for | Ultimaker PC, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS (file v5.00), April 20, 2022. | Generic structural steel, cited as ASTM A992 (the current US structural grade): ASTM A992 W-shapes; Fy/Fu specified minimums from AISC publications (AISC 360-16 Commentary; Modern Steel Construction); elastic constants AISC 360; physical constants from the bauforumstahl structural-steel EPD, which names A992 among covered product standards. |
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 Polycarbonate is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is FDM Polycarbonate stronger than Steel?
Steel is stronger: its yield strength is 385 MPa against 53.3 MPa for FDM Polycarbonate (7.22x).
Which is lighter, FDM Polycarbonate or Steel?
FDM Polycarbonate is lighter: 1,190 kg/m³ against 7,850 kg/m³ for Steel.
Which is stiffer, FDM Polycarbonate or Steel?
Steel is stiffer: Young's modulus 200 GPa against 2.39 GPa for FDM Polycarbonate, so the same part in Steel deflects less under the same load.
Which is lighter for the same job, FDM Polycarbonate or Steel?
For the same stiffness or strength: FDM Polycarbonate is lighter for a stiff panel or plate, strong beam, strong panel or plate; Steel is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie.
| Part that must be | FDM Polycarbonate | Steel |
|---|---|---|
| Stiff rod or tie (tension) | 12.7x heavier | lighter |
| Stiff beam (bending) | 39% heavier | lighter |
| Stiff panel or plate | lighter | 1.51x heavier |
| Strong rod or tie | 9% heavier | lighter |
| Strong beam | lighter | 1.77x heavier |
| Strong panel or plate | lighter | 2.45x 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, FDM Polycarbonate or Steel?
Steel conducts heat better: 48 W/m·K against 0.2 W/m·K for FDM Polycarbonate.
Which expands less with temperature?
Steel expands less: 12 µm/m·K against 65 µm/m·K for FDM Polycarbonate.