Materials / Compare
Iron vs. Magnesium AZ31B-H24
Compare Iron vs. Magnesium AZ31B-H24 strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 186MPasourcetypical (0.2% YS), hot rolled + SRA/recrystallization anneal | 220MPasourcetypical, H24, 0.5-6 mm, 0.2 % proof stress |
| Ultimate tensile strength | 290MPasourcetypical, SRA/recrystallization anneal | 290MPasourcetypical, H24, 0.5-6 mm |
| Elongation at break | 38%sourcetypical, gauge 4D0 | 13%sourcetypical, H24, 0.5-6 mm, gauge 5.65√A |
| Young's modulus (stiffness) | 207GPasourcetypical, after SRA/recrystallization anneal | 44.8GPasourcetypical (handbook physical constant) |
| Density | 7,860kg/m³sourcetypical | 1,769kg/m³sourcenominal |
| Strength to weight | 23.7kN·m/kg | 124kN·m/kg5.26x higher |
| Stiffness to weight | 26.3MN·m/kg4% higher | 25.3MN·m/kg |
| Poisson's ratio | 0.282sourceNIST critically evaluated best value (polycrystalline iron) | 0.35sourcetypical (handbook physical constant) |
| Shear modulus | 80.7GPa4.87x stiffer in shear | 16.6GPa |
| Bulk modulus | 158GPa | 49.8GPa |
| Speed of sound | 5,132m/s | 5,032m/s |
| Thermal | ||
| Thermal conductivity | 73.2W/m·Ksourcetypical at 20 °C | 76.9W/m·Ksourcetypical (temper/temperature not stated) |
| Thermal expansion | 13.7µm/m·Ksourcemean, 20-399 °C | 26.8µm/m·Ksourcetypical (temperature range not stated) |
| 100 mm part over a 50 °C swing | 68.5µm growth1.96x less | 134µm growth |
| Specific heat | 450J/kg·Ksourcetypical | 1,040J/kg·Ksourcetypical |
| Heats up and cools (diffusivity) | 20.7mm²/s | 41.8mm²/s2.02x faster |
| Thermal shock resistance | 3,447W/m | 9,159W/m2.66x more resistant |
| Melting point | 1,532°Csourcetypical | not sourced |
| Max service temperature | not sourced | 149°Csourcestated application limit |
| 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. | AZ31B-H24 sheet 0.016-0.062 in., MIL-HDBK-5J Table 4.2.1.0(b) (AMS 4377); strengths are S-basis MINIMUMS |
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 Magnesium AZ31B-H24?
Magnesium AZ31B-H24 is stronger: its yield strength is 220 MPa against 186 MPa for Iron (18%).
Which is lighter, Iron or Magnesium AZ31B-H24?
Magnesium AZ31B-H24 is lighter: 1,769 kg/m³ against 7,860 kg/m³ for Iron.
Which is stiffer, Iron or Magnesium AZ31B-H24?
Iron is stiffer: Young's modulus 207 GPa against 44.8 GPa for Magnesium AZ31B-H24, so the same part in Iron deflects less under the same load.
Which is lighter for the same job, Iron or Magnesium AZ31B-H24?
For the same stiffness or strength: Iron is lighter for a stiff rod or tie (tension); Magnesium AZ31B-H24 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 | Magnesium AZ31B-H24 |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 4% heavier |
| Stiff beam (bending) | 2.07x heavier | lighter |
| Stiff panel or plate | 2.67x heavier | lighter |
| Strong rod or tie | 5.26x heavier | lighter |
| Strong beam | 4.97x heavier | lighter |
| Strong panel or plate | 4.83x 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 Magnesium AZ31B-H24?
Magnesium AZ31B-H24 conducts heat better: 76.9 W/m·K against 73.2 W/m·K for Iron.
Which expands less with temperature?
Iron expands less: 13.7 µm/m·K against 26.8 µm/m·K for Magnesium AZ31B-H24.