Materials / Compare
Steel AISI 1045 vs. Plastic UHMWPE
Compare Steel AISI 1045 vs. Plastic UHMWPE 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 | 531MPasourceproducer-stated, cold drawn | 20MPasourcetypical, tensile stress at yield ISO 527, 50 mm/min |
| Ultimate tensile strength | 627MPasourceproducer-stated, cold drawn | 43MPasourcetypical, tensile stress at break ISO 527, 50 mm/min |
| Elongation at break | 12%sourcein 2 in (50.8 mm) | 465%sourcetypical, nominal elongation at break ISO 527 |
| Young's modulus (stiffness) | 210GPasourcetypical | 0.66GPasourcetypical, tensile modulus ISO 527, 1 mm/min |
| Density | 7,800kg/m³sourcetypical | 930kg/m³sourcetypical8.39x lighter |
| Strength to weight | 68.1kN·m/kg3.17x higher | 21.5kN·m/kg |
| Stiffness to weight | 26.9MN·m/kg37.9x higher | 0.71MN·m/kg |
| Poisson's ratio | 0.3sourcetypical | not sourced |
| Shear modulus | 80.8GPa | not sourced |
| Bulk modulus | 175GPa | not sourced |
| Speed of sound | 5,189m/s | 842m/s |
| Thermal | ||
| Thermal conductivity | 40–45W/m·Ksourcetypical range, ambient | 0.4W/m·Ksourcetypical, unfilled (narrative value, generic Celanese UHMWPE) |
| Thermal expansion | 12µm/m·Ksourcetypical, mean 20-300 °C | 200µm/m·Ksourcetypical, 20 to 100 °C (generic Celanese UHMWPE) |
| 100 mm part over a 50 °C swing | 60µm growth16.7x less | 1,000µm growth |
| Specific heat | 460–480J/kg·Ksourcetypical range, 50/100 °C | not sourced |
| Heats up and cools (diffusivity) | 11.6mm²/s | not sourced |
| Thermal shock resistance | 6,269W/m | not sourced |
| Melting point | not sourced | 130–138°CsourceDSC 10 K/min |
| Max service temperature | not sourced | 80°Csourcerecommended max constant operating temperature |
| Values for | AISI 1045 cold drawn bar (Niagara LaSalle) for mechanical; Ovako C45 (lists 'SAE 1045' as a similar designation) for physical constants | Celanese GUR 4120 (avg. molecular weight 4.7x10^6 g/mol), typical values on compression-molded specimens; CTE and thermal conductivity from Celanese's generic UHMWPE guide (grade not named) |
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 Steel AISI 1045 stronger than Plastic UHMWPE?
Steel AISI 1045 is stronger: its yield strength is 531 MPa against 20 MPa for Plastic UHMWPE (26.6x).
Which is lighter, Steel AISI 1045 or Plastic UHMWPE?
Plastic UHMWPE is lighter: 930 kg/m³ against 7,800 kg/m³ for Steel AISI 1045.
Which is stiffer, Steel AISI 1045 or Plastic UHMWPE?
Steel AISI 1045 is stiffer: Young's modulus 210 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Steel AISI 1045 deflects less under the same load.
Which is lighter for the same job, Steel AISI 1045 or Plastic UHMWPE?
For the same stiffness or strength: Steel AISI 1045 is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie, strong beam; Plastic UHMWPE is lighter for a stiff panel or plate, strong panel or plate.
| Part that must be | Steel AISI 1045 | Plastic UHMWPE |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 37.9x heavier |
| Stiff beam (bending) | lighter | 2.13x heavier |
| Stiff panel or plate | 23% heavier | lighter |
| Strong rod or tie | lighter | 3.17x heavier |
| Strong beam | lighter | 6% heavier |
| Strong panel or plate | 1.63x 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, Steel AISI 1045 or Plastic UHMWPE?
Steel AISI 1045 conducts heat better: 42.5 W/m·K against 0.4 W/m·K for Plastic UHMWPE.
Which expands less with temperature?
Steel AISI 1045 expands less: 12 µm/m·K against 200 µm/m·K for Plastic UHMWPE.