1100-O (annealed) commercially pure aluminium, Kaiser Aluminum Tube & Pipe Alloy 1100 Technical Data (Rev. 05/06), typical properties; specific heat from Hydro EN AW-1050A (99.5% Al) extruded-products datasheet (10/2018).
LyondellBasell Moplen HP501H polypropylene homopolymer (general purpose), typical ISO 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 1100-O stronger than Plastic Polypropylene?
Aluminum 1100-O is stronger: its yield strength is 35 MPa against 33 MPa for Plastic Polypropylene (6%).
Which is lighter, Aluminum 1100-O or Plastic Polypropylene?
Plastic Polypropylene is lighter: 900 kg/m³ against 2,710 kg/m³ for Aluminum 1100-O.
Which is stiffer, Aluminum 1100-O or Plastic Polypropylene?
Aluminum 1100-O is stiffer: Young's modulus 69 GPa against 1.45 GPa for Plastic Polypropylene, so the same part in Aluminum 1100-O deflects less under the same load.
Which is lighter for the same job, Aluminum 1100-O or Plastic Polypropylene?
For the same stiffness or strength: Aluminum 1100-O is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic Polypropylene is lighter for a strong rod or tie, strong beam, strong panel or plate.
Part that must be
Aluminum 1100-O
Plastic Polypropylene
Stiff rod or tie (tension)
lighter
15.8x heavier
Stiff beam (bending)
lighter
2.29x heavier
Stiff panel or plate
lighter
20% heavier
Strong rod or tie
2.84x heavier
lighter
Strong beam
2.9x heavier
lighter
Strong panel or plate
2.92x 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, Aluminum 1100-O or Plastic Polypropylene?
Aluminum 1100-O conducts heat better: 222 W/m·K against 0.195 W/m·K for Plastic Polypropylene.
Which expands less with temperature?
Aluminum 1100-O expands less: 23.6 µm/m·K against 90 µm/m·K for Plastic Polypropylene.