Austempered Cast Iron vs. AZ91B Magnesium
Austempered cast iron belongs to the iron alloys classification, while AZ91B magnesium belongs to the magnesium alloys. There are 26 material properties with values for both materials. Properties with values for just one material (7, in this case) are not shown. Please note that the two materials have significantly dissimilar densities. This means that additional care is required when interpreting the data, because some material properties are based on units of mass, while others are based on units of area or volume.
For each property being compared, the top bar is austempered cast iron and the bottom bar is AZ91B magnesium.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 270 to 490 | |
| 63 |
| Elastic (Young's, Tensile) Modulus, GPa | 180 | |
| 46 |
| Elongation at Break, % | 1.1 to 13 | |
| 5.0 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 62 to 69 | |
| 18 |
| Tensile Strength: Ultimate (UTS), MPa | 860 to 1800 | |
| 240 |
| Tensile Strength: Yield (Proof), MPa | 560 to 1460 | |
| 160 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 360 |
| Melting Completion (Liquidus), °C | 1380 | |
| 600 |
| Melting Onset (Solidus), °C | 1340 | |
| 470 |
| Specific Heat Capacity, J/kg-K | 490 | |
| 990 |
| Thermal Conductivity, W/m-K | 42 | |
| 73 |
| Thermal Expansion, µm/m-K | 13 | |
| 26 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.9 | |
| 12 |
| Density, g/cm3 | 7.5 | |
| 1.7 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 22 |
| Embodied Energy, MJ/kg | 25 | |
| 160 |
| Embodied Water, L/kg | 48 | |
| 990 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 19 to 95 | |
| 11 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 880 to 3970 | |
| 280 |
| Stiffness to Weight: Axial, points | 13 | |
| 15 |
| Stiffness to Weight: Bending, points | 25 | |
| 69 |
| Strength to Weight: Axial, points | 32 to 66 | |
| 38 |
| Strength to Weight: Bending, points | 27 to 44 | |
| 49 |
| Thermal Diffusivity, mm2/s | 11 | |
| 42 |
| Thermal Shock Resistance, points | 25 to 53 | |
| 14 |
Alloy Composition
| Aluminum (Al), % | 0 to 0.050 | |
| 8.3 to 9.7 |
| Arsenic (As), % | 0 to 0.020 | |
| 0 |
| Carbon (C), % | 3.4 to 3.8 | |
| 0 |
| Chromium (Cr), % | 0 to 0.1 | |
| 0 |
| Copper (Cu), % | 0 to 0.8 | |
| 0 to 0.35 |
| Iron (Fe), % | 89.6 to 94 | |
| 0 |
| Magnesium (Mg), % | 0 to 0.040 | |
| 87.9 to 91.2 |
| Manganese (Mn), % | 0.3 to 0.4 | |
| 0.13 to 0.5 |
| Molybdenum (Mo), % | 0 to 0.3 | |
| 0 |
| Nickel (Ni), % | 0 to 2.0 | |
| 0 to 0.030 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 |
| Selenium (Se), % | 0 to 0.030 | |
| 0 |
| Silicon (Si), % | 2.3 to 2.7 | |
| 0 to 0.5 |
| Sulfur (S), % | 0 to 0.020 | |
| 0 |
| Tin (Sn), % | 0 to 0.020 | |
| 0 |
| Vanadium (V), % | 0 to 0.1 | |
| 0 |
| Zinc (Zn), % | 0 | |
| 0.35 to 1.0 |