7021 Aluminum vs. Automotive Malleable Cast Iron
7021 aluminum belongs to the aluminum alloys classification, while automotive malleable cast iron belongs to the iron alloys. There are 27 material properties with values for both materials. Properties with values for just one material (4, 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 7021 aluminum and the bottom bar is automotive malleable cast iron.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 69 | |
| 180 |
| Elongation at Break, % | 9.4 | |
| 1.0 to 10 |
| Poisson's Ratio | 0.32 | |
| 0.29 |
| Shear Modulus, GPa | 26 | |
| 70 |
| Tensile Strength: Ultimate (UTS), MPa | 460 | |
| 350 to 720 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 220 to 590 |
Thermal Properties
| Latent Heat of Fusion, J/g | 380 | |
| 260 |
| Melting Completion (Liquidus), °C | 630 | |
| 1410 |
| Melting Onset (Solidus), °C | 510 | |
| 1370 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 480 |
| Thermal Conductivity, W/m-K | 150 | |
| 41 |
| Thermal Expansion, µm/m-K | 24 | |
| 14 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 38 | |
| 7.4 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 120 | |
| 8.7 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 1.9 |
| Density, g/cm3 | 2.9 | |
| 7.6 |
| Embodied Carbon, kg CO2/kg material | 8.3 | |
| 1.5 |
| Embodied Energy, MJ/kg | 150 | |
| 20 |
| Embodied Water, L/kg | 1140 | |
| 45 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 41 | |
| 6.8 to 30 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1110 | |
| 130 to 950 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 47 | |
| 25 |
| Strength to Weight: Axial, points | 44 | |
| 13 to 26 |
| Strength to Weight: Bending, points | 45 | |
| 14 to 24 |
| Thermal Diffusivity, mm2/s | 59 | |
| 11 |
| Thermal Shock Resistance, points | 20 | |
| 9.9 to 21 |
Alloy Composition
| Aluminum (Al), % | 90.7 to 93.7 | |
| 0 |
| Carbon (C), % | 0 | |
| 2.2 to 2.9 |
| Chromium (Cr), % | 0 to 0.050 | |
| 0 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 |
| Iron (Fe), % | 0 to 0.4 | |
| 93.6 to 96.7 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 0 |
| Manganese (Mn), % | 0 to 0.1 | |
| 0.15 to 1.3 |
| Phosphorus (P), % | 0 | |
| 0.020 to 0.15 |
| Silicon (Si), % | 0 to 0.25 | |
| 0.9 to 1.9 |
| Sulfur (S), % | 0 | |
| 0.020 to 0.2 |
| Titanium (Ti), % | 0 to 0.1 | |
| 0 |
| Zinc (Zn), % | 5.0 to 6.0 | |
| 0 |
| Zirconium (Zr), % | 0.080 to 0.18 | |
| 0 |
| Residuals, % | 0 to 0.15 | |
| 0 |