Materials / Compare
Stainless 303 vs. Zinc Zamak 3
Compare Stainless 303 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 | 275MPasourceOutokumpu typical (product P = hot rolled plate, transverse) | 221MPasourcetypical |
| Ultimate tensile strength | 585MPasourceOutokumpu typical | 283MPasourcetypical |
| Elongation at break | 35%sourceOutokumpu typical, A5 | 10%sourcetypical, in 2 in. |
| Young's modulus (stiffness) | 200GPasourceat RT (Table 12) | 85.5GPasourcetypical |
| Density | 7,900kg/m³sourceat RT | 6,600kg/m³sourcetypical |
| Strength to weight | 34.8kN·m/kg4% higher | 33.5kN·m/kg |
| Stiffness to weight | 25.3MN·m/kg1.95x higher | 13MN·m/kg |
| Poisson's ratio | 0.3sourcedesign value (structural stainless steels) | 0.27sourcetypical, Zamak 3 hot-chamber die cast |
| Shear modulus | 76.9GPa2.29x stiffer in shear | 33.7GPa |
| Bulk modulus | 167GPa | 62GPa |
| Speed of sound | 5,032m/s | 3,599m/s |
| Thermal | ||
| Thermal conductivity | 15W/m·Ksourceat RT | 113W/m·Ksourcetypical |
| Thermal expansion | 16µm/m·Ksourcemean, 20–100 °C | 27.4µm/m·Ksourcetypical |
| 100 mm part over a 50 °C swing | 80µm growth1.71x less | 137µm growth |
| Specific heat | 500J/kg·Ksourceat RT | 419J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | 3.8mm²/s | 40.9mm²/s10.8x faster |
| Thermal shock resistance | 902W/m | 7,782W/m8.62x more resistant |
| Melting point | not sourced | 381–387°Csourcemelting range |
| Max service temperature | 871°Csourcecontinuous, scaling limit | not sourced |
| Values for | 1.4305 / UNS S30300, Outokumpu typical values (hot rolled, solution annealed) from 'Steel Grades, Properties and Global Standards'; max service from Carpenter CarTech 303 datasheet | 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 303 stronger than Zinc Zamak 3?
Stainless 303 is stronger: its yield strength is 275 MPa against 221 MPa for Zinc Zamak 3 (24%).
Which is lighter, Stainless 303 or Zinc Zamak 3?
Zinc Zamak 3 is lighter: 6,600 kg/m³ against 7,900 kg/m³ for Stainless 303.
Which is stiffer, Stainless 303 or Zinc Zamak 3?
Stainless 303 is stiffer: Young's modulus 200 GPa against 85.5 GPa for Zinc Zamak 3, so the same part in Stainless 303 deflects less under the same load.
Which is lighter for the same job, Stainless 303 or Zinc Zamak 3?
For the same stiffness or strength: Stainless 303 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie; Zinc Zamak 3 is lighter for a strong beam, strong panel or plate.
| Part that must be | Stainless 303 | Zinc Zamak 3 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 1.95x heavier |
| Stiff beam (bending) | lighter | 28% heavier |
| Stiff panel or plate | lighter | 11% heavier |
| Strong rod or tie | lighter | 4% heavier |
| Strong beam | 3% heavier | lighter |
| Strong panel or plate | 7% 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 303 or Zinc Zamak 3?
Zinc Zamak 3 conducts heat better: 113 W/m·K against 15 W/m·K for Stainless 303.
Which expands less with temperature?
Stainless 303 expands less: 16 µm/m·K against 27.4 µm/m·K for Zinc Zamak 3.