2218 Aluminum vs. AZ91C Magnesium
2218 aluminum belongs to the aluminum alloys classification, while AZ91C magnesium belongs to the magnesium alloys. There are 30 material properties with values for both materials. Properties with values for just one material (2, in this case) are not shown.
For each property being compared, the top bar is 2218 aluminum and the bottom bar is AZ91C magnesium.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 73 | |
| 46 |
| Elongation at Break, % | 6.8 to 10 | |
| 2.3 to 7.9 |
| Fatigue Strength, MPa | 110 | |
| 56 to 85 |
| Poisson's Ratio | 0.33 | |
| 0.29 |
| Shear Modulus, GPa | 27 | |
| 18 |
| Shear Strength, MPa | 210 to 250 | |
| 96 to 160 |
| Tensile Strength: Ultimate (UTS), MPa | 330 to 430 | |
| 170 to 270 |
| Tensile Strength: Yield (Proof), MPa | 260 to 310 | |
| 83 to 130 |
Thermal Properties
| Latent Heat of Fusion, J/g | 390 | |
| 350 |
| Maximum Temperature: Mechanical, °C | 220 | |
| 130 |
| Melting Completion (Liquidus), °C | 640 | |
| 600 |
| Melting Onset (Solidus), °C | 510 | |
| 470 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 990 |
| Thermal Conductivity, W/m-K | 140 | |
| 73 |
| Thermal Expansion, µm/m-K | 22 | |
| 26 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 37 | |
| 9.9 to 12 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 110 | |
| 52 to 60 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 11 | |
| 12 |
| Density, g/cm3 | 3.1 | |
| 1.7 |
| Embodied Carbon, kg CO2/kg material | 8.2 | |
| 22 |
| Embodied Energy, MJ/kg | 150 | |
| 160 |
| Embodied Water, L/kg | 1130 | |
| 990 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 27 to 31 | |
| 3.2 to 16 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 450 to 650 | |
| 75 to 180 |
| Stiffness to Weight: Axial, points | 13 | |
| 15 |
| Stiffness to Weight: Bending, points | 45 | |
| 69 |
| Strength to Weight: Axial, points | 30 to 39 | |
| 27 to 43 |
| Strength to Weight: Bending, points | 34 to 41 | |
| 39 to 53 |
| Thermal Diffusivity, mm2/s | 52 | |
| 43 |
| Thermal Shock Resistance, points | 15 to 19 | |
| 9.9 to 16 |
Alloy Composition
| Aluminum (Al), % | 88.8 to 93.6 | |
| 8.1 to 9.3 |
| Chromium (Cr), % | 0 to 0.1 | |
| 0 |
| Copper (Cu), % | 3.5 to 4.5 | |
| 0 to 0.1 |
| Iron (Fe), % | 0 to 1.0 | |
| 0 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 88.6 to 91.4 |
| Manganese (Mn), % | 0 to 0.2 | |
| 0.13 to 0.35 |
| Nickel (Ni), % | 1.7 to 2.3 | |
| 0 to 0.010 |
| Silicon (Si), % | 0 to 0.9 | |
| 0 to 0.3 |
| Zinc (Zn), % | 0 to 0.25 | |
| 0.4 to 1.0 |
| Residuals, % | 0 | |
| 0 to 0.3 |