Materials / Compare
Plastic UHMWPE vs. Zinc Zamak 3
Compare Plastic UHMWPE vs. Zinc Zamak 3 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 | 20MPasourcetypical, tensile stress at yield ISO 527, 50 mm/min | 221MPasourcetypical |
| Ultimate tensile strength | 43MPasourcetypical, tensile stress at break ISO 527, 50 mm/min | 283MPasourcetypical |
| Elongation at break | 465%sourcetypical, nominal elongation at break ISO 527 | 10%sourcetypical, in 2 in. |
| Young's modulus (stiffness) | 0.66GPasourcetypical, tensile modulus ISO 527, 1 mm/min | 85.5GPasourcetypical |
| Density | 930kg/m³sourcetypical7.1x lighter | 6,600kg/m³sourcetypical |
| Strength to weight | 21.5kN·m/kg | 33.5kN·m/kg1.56x higher |
| Stiffness to weight | 0.71MN·m/kg | 13MN·m/kg18.3x higher |
| Poisson's ratio | not sourced | 0.27sourcetypical, Zamak 3 hot-chamber die cast |
| Shear modulus | not sourced | 33.7GPa |
| Bulk modulus | not sourced | 62GPa |
| Speed of sound | 842m/s | 3,599m/s |
| Thermal | ||
| Thermal conductivity | 0.4W/m·Ksourcetypical, unfilled (narrative value, generic Celanese UHMWPE) | 113W/m·Ksourcetypical |
| Thermal expansion | 200µm/m·Ksourcetypical, 20 to 100 °C (generic Celanese UHMWPE) | 27.4µm/m·Ksourcetypical |
| 100 mm part over a 50 °C swing | 1,000µm growth | 137µm growth7.3x less |
| Specific heat | not sourced | 419J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | not sourced | 40.9mm²/s |
| Thermal shock resistance | not sourced | 7,782W/m |
| Melting point | 130–138°CsourceDSC 10 K/min | 381–387°Csourcemelting range |
| Max service temperature | 80°Csourcerecommended max constant operating temperature | not sourced |
| Values for | 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) | Zamak 3 (ASTM B86 die cast), Nathan Trotter (zinc alloy producer) technical data sheet, typical values |
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 UHMWPE stronger than Zinc Zamak 3?
Zinc Zamak 3 is stronger: its yield strength is 221 MPa against 20 MPa for Plastic UHMWPE (11.1x).
Which is lighter, Plastic UHMWPE or Zinc Zamak 3?
Plastic UHMWPE is lighter: 930 kg/m³ against 6,600 kg/m³ for Zinc Zamak 3.
Which is stiffer, Plastic UHMWPE or Zinc Zamak 3?
Zinc Zamak 3 is stiffer: Young's modulus 85.5 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Zinc Zamak 3 deflects less under the same load.
Which is lighter for the same job, Plastic UHMWPE or Zinc Zamak 3?
For the same stiffness or strength: Plastic UHMWPE is lighter for a stiff panel or plate, strong beam, strong panel or plate; Zinc Zamak 3 is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie.
| Part that must be | Plastic UHMWPE | Zinc Zamak 3 |
|---|---|---|
| Stiff rod or tie (tension) | 18.3x heavier | lighter |
| Stiff beam (bending) | 1.6x heavier | lighter |
| Stiff panel or plate | lighter | 40% heavier |
| Strong rod or tie | 1.56x heavier | lighter |
| Strong beam | lighter | 43% heavier |
| Strong panel or plate | lighter | 2.13x 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 UHMWPE or Zinc Zamak 3?
Zinc Zamak 3 conducts heat better: 113 W/m·K against 0.4 W/m·K for Plastic UHMWPE.
Which expands less with temperature?
Zinc Zamak 3 expands less: 27.4 µm/m·K against 200 µm/m·K for Plastic UHMWPE.