A380 aluminium high-pressure die-casting alloy, typical properties; Rheocast Company (aluminium die caster, Germantown WI) A380 alloy data page.
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 Aluminum A380 stronger than Zinc Zamak 3?
Zinc Zamak 3 is stronger: its yield strength is 221 MPa against 160 MPa for Aluminum A380 (38%).
Which is lighter, Aluminum A380 or Zinc Zamak 3?
Aluminum A380 is lighter: 2,713 kg/m³ against 6,600 kg/m³ for Zinc Zamak 3.
Which is stiffer, Aluminum A380 or Zinc Zamak 3?
Zinc Zamak 3 is stiffer: Young's modulus 85.5 GPa against 71 GPa for Aluminum A380, so the same part in Zinc Zamak 3 deflects less under the same load.
Which is lighter for the same job, Aluminum A380 or Zinc Zamak 3?
For the same stiffness or strength: Aluminum A380 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
Part that must be
Aluminum A380
Zinc Zamak 3
Stiff rod or tie (tension)
lighter
2.02x heavier
Stiff beam (bending)
lighter
2.22x heavier
Stiff panel or plate
lighter
2.29x heavier
Strong rod or tie
lighter
1.76x heavier
Strong beam
lighter
1.96x heavier
Strong panel or plate
lighter
2.07x 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, Aluminum A380 or Zinc Zamak 3?
Zinc Zamak 3 conducts heat better: 113 W/m·K against 96.2 W/m·K for Aluminum A380.
Which expands less with temperature?
Aluminum A380 expands less: 21.8 µm/m·K against 27.4 µm/m·K for Zinc Zamak 3.