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.
BASF Ultradur B 4300 G6 (PBT, 30% glass fibre), injection moulding grade; product information sheet 09/2026, typical values for uncoloured product at 23 °C.
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 PBT GF30?
Iron is stronger: its yield strength is 186 MPa against tensile strength 140 MPa for Plastic PBT GF30 (33%).
Which is lighter, Iron or Plastic PBT GF30?
Plastic PBT GF30 is lighter: 1,530 kg/m³ against 7,860 kg/m³ for Iron.
Which is stiffer, Iron or Plastic PBT GF30?
Iron is stiffer: Young's modulus 207 GPa against 9.8 GPa for Plastic PBT GF30, so the same part in Iron deflects less under the same load.
Which is lighter for the same job, Iron or Plastic PBT GF30?
For the same stiffness or strength: Iron is lighter for a stiff rod or tie (tension); Plastic PBT GF30 is lighter for a stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
Part that must be
Iron
Plastic PBT GF30
Stiff rod or tie (tension)
lighter
4.11x heavier
Stiff beam (bending)
12% heavier
lighter
Stiff panel or plate
1.86x heavier
lighter
Strong rod or tie
3.87x heavier
lighter
Strong beam
4.25x heavier
lighter
Strong panel or plate
4.46x 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 PBT GF30?
Iron conducts heat better: 73.2 W/m·K against 0.27 W/m·K for Plastic PBT GF30.
Which expands less with temperature?
Iron expands less: 13.7 µm/m·K against 25 µm/m·K for Plastic PBT GF30.