6063-T6 extruded tube, Kaiser Aluminum Tube & Pipe Alloy 6063 Technical Data (Rev. 05/06), typical properties; specific heat from Hydro EN AW-6063 extruded-products datasheet (Rev.4, 03/2023).
Ultimaker PETG, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS v1.00, April 29, 2022.
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.
Plastic PETG is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Aluminum 6063-T6 stronger than Plastic PETG?
Aluminum 6063-T6 is stronger: its yield strength is 215 MPa against 46.2 MPa for Plastic PETG (4.65x).
Which is lighter, Aluminum 6063-T6 or Plastic PETG?
Plastic PETG is lighter: 1,270 kg/m³ against 2,700 kg/m³ for Aluminum 6063-T6.
Which is stiffer, Aluminum 6063-T6 or Plastic PETG?
Aluminum 6063-T6 is stiffer: Young's modulus 69 GPa against 1.94 GPa for Plastic PETG, so the same part in Aluminum 6063-T6 deflects less under the same load.
Which is lighter for the same job, Aluminum 6063-T6 or Plastic PETG?
For the same stiffness or strength: Aluminum 6063-T6 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 6063-T6
Plastic PETG
Stiff rod or tie (tension)
lighter
16.7x heavier
Stiff beam (bending)
lighter
2.81x heavier
Stiff panel or plate
lighter
1.55x heavier
Strong rod or tie
lighter
2.19x heavier
Strong beam
lighter
31% heavier
Strong panel or plate
lighter
1% 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 6063-T6 or Plastic PETG?
Aluminum 6063-T6 conducts heat better: 201 W/m·K against 0.21 W/m·K for Plastic PETG.
Which expands less with temperature?
Aluminum 6063-T6 expands less: 23.4 µm/m·K against 51 µm/m·K for Plastic PETG.