A380 aluminium high-pressure die-casting alloy, typical properties; Rheocast Company (aluminium die caster, Germantown WI) A380 alloy data page.
DuPont Delrin 100 acetal homopolymer, Table 2 'Typical Properties of Delrin Acetal Resins' (ASTM methods), Delrin Design Guide Module III hosted on delrin.com
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 Plastic POM/Acetal?
Aluminum A380 is stronger: its yield strength is 160 MPa against 69 MPa for Plastic POM/Acetal (2.32x).
Which is lighter, Aluminum A380 or Plastic POM/Acetal?
Plastic POM/Acetal is lighter: 1,420 kg/m³ against 2,713 kg/m³ for Aluminum A380.
Which is stiffer, Aluminum A380 or Plastic POM/Acetal?
Aluminum A380 is stiffer: Young's modulus 71 GPa against 2.8 GPa for Plastic POM/Acetal, so the same part in Aluminum A380 deflects less under the same load.
Which is lighter for the same job, Aluminum A380 or Plastic POM/Acetal?
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; Plastic POM/Acetal is lighter for a strong beam, strong panel or plate.
Part that must be
Aluminum A380
Plastic POM/Acetal
Stiff rod or tie (tension)
lighter
13.3x heavier
Stiff beam (bending)
lighter
2.64x heavier
Stiff panel or plate
lighter
1.54x heavier
Strong rod or tie
lighter
21% heavier
Strong beam
9% heavier
lighter
Strong panel or plate
25% 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 is more ductile, Aluminum A380 or Plastic POM/Acetal?
Plastic POM/Acetal stretches further before it breaks: 75% elongation at break against 3.5% for Aluminum A380.
Which conducts heat better, Aluminum A380 or Plastic POM/Acetal?
Aluminum A380 conducts heat better: 96.2 W/m·K against 0.4 W/m·K for Plastic POM/Acetal.
Which expands less with temperature?
Aluminum A380 expands less: 21.8 µm/m·K against 122 µm/m·K for Plastic POM/Acetal.