A380 aluminium high-pressure die-casting alloy, typical properties; Rheocast Company (aluminium die caster, Germantown WI) A380 alloy data page.
Röhm PLEXIGLAS GS 0F00 cast acrylic sheet, typical values at 23 °C / 50 % RH (Röhm Technical Information Ref. No. 211-1)
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 PMMA?
Aluminum A380 is stronger: its yield strength is 160 MPa against tensile strength 80 MPa for Plastic PMMA (2x).
Which is lighter, Aluminum A380 or Plastic PMMA?
Plastic PMMA is lighter: 1,190 kg/m³ against 2,713 kg/m³ for Aluminum A380.
Which is stiffer, Aluminum A380 or Plastic PMMA?
Aluminum A380 is stiffer: Young's modulus 71 GPa against 3.3 GPa for Plastic PMMA, so the same part in Aluminum A380 deflects less under the same load.
Which is lighter for the same job, Aluminum A380 or Plastic PMMA?
For the same stiffness or strength: Aluminum A380 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic PMMA is lighter for a strong rod or tie, strong beam, strong panel or plate.
Part that must be
Aluminum A380
Plastic PMMA
Stiff rod or tie (tension)
lighter
9.44x heavier
Stiff beam (bending)
lighter
2.03x heavier
Stiff panel or plate
lighter
22% heavier
Strong rod or tie
14% heavier
lighter
Strong beam
44% heavier
lighter
Strong panel or plate
1.61x 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 PMMA?
Plastic PMMA stretches further before it breaks: 5.5% elongation at break against 3.5% for Aluminum A380.
Which conducts heat better, Aluminum A380 or Plastic PMMA?
Aluminum A380 conducts heat better: 96.2 W/m·K against 0.19 W/m·K for Plastic PMMA.
Which expands less with temperature?
Aluminum A380 expands less: 21.8 µm/m·K against 70 µm/m·K for Plastic PMMA.