AZ91B Magnesium vs. ACI-ASTM CB7Cu-1 Steel
AZ91B magnesium belongs to the magnesium alloys classification, while ACI-ASTM CB7Cu-1 steel belongs to the iron alloys. There are 29 material properties with values for both materials. Properties with values for just one material (6, 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 AZ91B magnesium and the bottom bar is ACI-ASTM CB7Cu-1 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 63 | |
| 300 to 420 |
| Elastic (Young's, Tensile) Modulus, GPa | 46 | |
| 190 |
| Elongation at Break, % | 5.0 | |
| 5.7 to 11 |
| Fatigue Strength, MPa | 79 | |
| 420 to 590 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 18 | |
| 76 |
| Tensile Strength: Ultimate (UTS), MPa | 240 | |
| 960 to 1350 |
| Tensile Strength: Yield (Proof), MPa | 160 | |
| 760 to 1180 |
Thermal Properties
| Latent Heat of Fusion, J/g | 360 | |
| 280 |
| Melting Completion (Liquidus), °C | 600 | |
| 1430 |
| Melting Onset (Solidus), °C | 470 | |
| 1500 |
| Specific Heat Capacity, J/kg-K | 990 | |
| 480 |
| Thermal Conductivity, W/m-K | 73 | |
| 17 |
| Thermal Expansion, µm/m-K | 26 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 11 | |
| 2.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 58 | |
| 2.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 12 | |
| 13 |
| Density, g/cm3 | 1.7 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 22 | |
| 2.6 |
| Embodied Energy, MJ/kg | 160 | |
| 38 |
| Embodied Water, L/kg | 990 | |
| 130 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 11 | |
| 71 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 280 | |
| 1500 to 3590 |
| Stiffness to Weight: Axial, points | 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 69 | |
| 25 |
| Strength to Weight: Axial, points | 38 | |
| 34 to 48 |
| Strength to Weight: Bending, points | 49 | |
| 28 to 35 |
| Thermal Diffusivity, mm2/s | 42 | |
| 4.6 |
| Thermal Shock Resistance, points | 14 | |
| 32 to 45 |
Alloy Composition
| Aluminum (Al), % | 8.3 to 9.7 | |
| 0 |
| Carbon (C), % | 0 | |
| 0 to 0.070 |
| Chromium (Cr), % | 0 | |
| 15.5 to 17.7 |
| Copper (Cu), % | 0 to 0.35 | |
| 2.5 to 3.2 |
| Iron (Fe), % | 0 | |
| 72.3 to 78.4 |
| Magnesium (Mg), % | 87.9 to 91.2 | |
| 0 |
| Manganese (Mn), % | 0.13 to 0.5 | |
| 0 to 0.7 |
| Nickel (Ni), % | 0 to 0.030 | |
| 3.6 to 4.6 |
| Niobium (Nb), % | 0 | |
| 0 to 0.35 |
| Nitrogen (N), % | 0 | |
| 0 to 0.050 |
| Phosphorus (P), % | 0 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Zinc (Zn), % | 0.35 to 1.0 | |
| 0 |