Materials / Compare
Stainless 304 vs. Zinc Zamak 3
Compare Stainless 304 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 | 241MPasourcetypical, annealed, 70 °F (21 °C) | 221MPasourcetypical |
| Ultimate tensile strength | 586MPasourcetypical, annealed, 70 °F (21 °C) | 283MPasourcetypical |
| Elongation at break | 55%sourcetypical, annealed, in 2 in. (50.8 mm) | 10%sourcetypical, in 2 in. |
| Young's modulus (stiffness) | 193GPasourcetypical, in tension | 85.5GPasourcetypical |
| Density | 8,030kg/m³sourcetypical | 6,600kg/m³sourcetypical22% lighter |
| Strength to weight | 30kN·m/kg | 33.5kN·m/kg12% higher |
| Stiffness to weight | 24MN·m/kg1.86x higher | 13MN·m/kg |
| Poisson's ratio | 0.3sourcedesign value (structural stainless steels) | 0.27sourcetypical, Zamak 3 hot-chamber die cast |
| Shear modulus | 74.2GPa2.21x stiffer in shear | 33.7GPa |
| Bulk modulus | 161GPa | 62GPa |
| Speed of sound | 4,903m/s | 3,599m/s |
| Thermal | ||
| Thermal conductivity | 16.2W/m·Ksourceat 100 °C | 113W/m·Ksourcetypical |
| Thermal expansion | 16.9µm/m·Ksourcemean, 0–100 °C | 27.4µm/m·Ksourcetypical |
| 100 mm part over a 50 °C swing | 84.5µm growth1.62x less | 137µm growth |
| Specific heat | 500J/kg·Ksourcemean, 0–100 °C | 419J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | 4.03mm²/s | 40.9mm²/s10.1x faster |
| Thermal shock resistance | 838W/m | 7,782W/m9.29x more resistant |
| Melting point | 1,399–1,454°Csourcemelting range | 381–387°Csourcemelting range |
| Max service temperature | 899°Csourcecontinuous, oxidation (scaling) limit in air | not sourced |
| Values for | Type 304, annealed flat-rolled (Cleveland-Cliffs 304/304L Product Data Bulletin, May 2021); Poisson's ratio from the Nickel Institute/SCI structural stainless design manual | 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 Stainless 304 stronger than Zinc Zamak 3?
Stainless 304 is stronger: its yield strength is 241 MPa against 221 MPa for Zinc Zamak 3 (9%).
Which is lighter, Stainless 304 or Zinc Zamak 3?
Zinc Zamak 3 is lighter: 6,600 kg/m³ against 8,030 kg/m³ for Stainless 304.
Which is stiffer, Stainless 304 or Zinc Zamak 3?
Stainless 304 is stiffer: Young's modulus 193 GPa against 85.5 GPa for Zinc Zamak 3, so the same part in Stainless 304 deflects less under the same load.
Which is lighter for the same job, Stainless 304 or Zinc Zamak 3?
For the same stiffness or strength: Stainless 304 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Zinc Zamak 3 is lighter for a strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Stainless 304 | Zinc Zamak 3 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 1.86x heavier |
| Stiff beam (bending) | lighter | 23% heavier |
| Stiff panel or plate | lighter | 8% heavier |
| Strong rod or tie | 12% heavier | lighter |
| Strong beam | 15% heavier | lighter |
| Strong panel or plate | 17% 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, Stainless 304 or Zinc Zamak 3?
Zinc Zamak 3 conducts heat better: 113 W/m·K against 16.2 W/m·K for Stainless 304.
Which expands less with temperature?
Stainless 304 expands less: 16.9 µm/m·K against 27.4 µm/m·K for Zinc Zamak 3.