80°Csourcerecommended max constant operating temperature
Values for
Cleveland-Cliffs / AK Steel ARMCO Pure Iron Product Data Bulletin (07/2022): Table 1 typical physical properties, Table 2 typical mechanical properties after SRA/recrystallization anneal.
Celanese GUR 4120 (avg. molecular weight 4.7x10^6 g/mol), typical values on compression-molded specimens; CTE and thermal conductivity from Celanese's generic UHMWPE guide (grade not named)
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 Iron stronger than Plastic UHMWPE?
Iron is stronger: its yield strength is 186 MPa against 20 MPa for Plastic UHMWPE (9.3x).
Which is lighter, Iron or Plastic UHMWPE?
Plastic UHMWPE is lighter: 930 kg/m³ against 7,860 kg/m³ for Iron.
Which is stiffer, Iron or Plastic UHMWPE?
Iron is stiffer: Young's modulus 207 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Iron deflects less under the same load.
Which is lighter for the same job, Iron or Plastic UHMWPE?
For the same stiffness or strength: Iron is lighter for a stiff rod or tie (tension), stiff beam (bending), strong rod or tie; Plastic UHMWPE is lighter for a stiff panel or plate, strong beam, strong panel or plate.
Part that must be
Iron
Plastic UHMWPE
Stiff rod or tie (tension)
lighter
37.1x heavier
Stiff beam (bending)
lighter
2.1x heavier
Stiff panel or plate
24% heavier
lighter
Strong rod or tie
lighter
10% heavier
Strong beam
1.91x heavier
lighter
Strong panel or plate
2.77x 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, Iron or Plastic UHMWPE?
Iron conducts heat better: 73.2 W/m·K against 0.4 W/m·K for Plastic UHMWPE.
Which expands less with temperature?
Iron expands less: 13.7 µm/m·K against 200 µm/m·K for Plastic UHMWPE.