Materials / Compare
Plastic Nylon PA66 vs. Zinc Zamak 3
Compare Plastic Nylon PA66 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 | 85MPasourcetypical, dry | 221MPasourcetypical |
| Ultimate tensile strength | not sourced | 283MPasourcetypical |
| Elongation at break | 30%sourcenominal strain at break, dry | 10%sourcetypical, in 2 in. |
| Young's modulus (stiffness) | 3GPasourcetypical, dry | 85.5GPasourcetypical |
| Density | 1,130kg/m³sourcetypical5.84x lighter | 6,600kg/m³sourcetypical |
| Strength to weight | 75.2kN·m/kg2.25x higher | 33.5kN·m/kg |
| Stiffness to weight | 2.65MN·m/kg | 13MN·m/kg4.88x higher |
| Poisson's ratio | 0.4sourcebase material: unfilled polyamide (PA), conditioned, maker design-guide family value (Covestro Table 3-1) | 0.27sourcetypical, Zamak 3 hot-chamber die cast |
| Shear modulus | 1.07GPa | 33.7GPa31.4x stiffer in shear |
| Bulk modulus | 5GPa | 62GPa |
| Speed of sound | 1,629m/s | 3,599m/s |
| Thermal | ||
| Thermal conductivity | 0.33W/m·Ksourcetypical | 113W/m·Ksourcetypical342x more heat through a fin |
| Thermal expansion | 98µm/m·Ksourcelongitudinal, 23-55 °C | 27.4µm/m·Ksourcetypical |
| 100 mm part over a 50 °C swing | 490µm growth | 137µm growth3.58x less |
| Specific heat | 1,700J/kg·Ksourcetypical | 419J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | 0.172mm²/s | 40.9mm²/s238x faster |
| Thermal shock resistance | 57.2W/m | 7,782W/m136x more resistant |
| Melting point | 260°CsourceDSC | 381–387°Csourcemelting range |
| Max service temperature | 101°CsourceIEC 60216 temperature index, 20000 h | not sourced |
| Values for | BASF Ultramid A3K (PA66, unreinforced injection-moulding grade), Product Information 02/2026, dry values (ISO methods) | 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 Nylon PA66 stronger than Zinc Zamak 3?
Zinc Zamak 3 is stronger: its yield strength is 221 MPa against 85 MPa for Plastic Nylon PA66 (2.6x).
Which is lighter, Plastic Nylon PA66 or Zinc Zamak 3?
Plastic Nylon PA66 is lighter: 1,130 kg/m³ against 6,600 kg/m³ for Zinc Zamak 3.
Which is stiffer, Plastic Nylon PA66 or Zinc Zamak 3?
Zinc Zamak 3 is stiffer: Young's modulus 85.5 GPa against 3 GPa for Plastic Nylon PA66, so the same part in Zinc Zamak 3 deflects less under the same load.
Which is lighter for the same job, Plastic Nylon PA66 or Zinc Zamak 3?
For the same stiffness or strength: Plastic Nylon PA66 is lighter for a stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate; Zinc Zamak 3 is lighter for a stiff rod or tie (tension).
| Part that must be | Plastic Nylon PA66 | Zinc Zamak 3 |
|---|---|---|
| Stiff rod or tie (tension) | 4.88x heavier | lighter |
| Stiff beam (bending) | lighter | 9% heavier |
| Stiff panel or plate | lighter | 1.91x heavier |
| Strong rod or tie | lighter | 2.25x heavier |
| Strong beam | lighter | 3.09x heavier |
| Strong panel or plate | lighter | 3.62x 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 Nylon PA66 or Zinc Zamak 3?
Zinc Zamak 3 conducts heat better: 113 W/m·K against 0.33 W/m·K for Plastic Nylon PA66.
Which expands less with temperature?
Zinc Zamak 3 expands less: 27.4 µm/m·K against 98 µm/m·K for Plastic Nylon PA66.