7021 Aluminum vs. Austempered Cast Iron
7021 aluminum belongs to the aluminum alloys classification, while austempered cast iron belongs to the iron alloys. There are 25 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 7021 aluminum and the bottom bar is austempered cast iron.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 69 | |
| 180 |
| Elongation at Break, % | 9.4 | |
| 1.1 to 13 |
| Poisson's Ratio | 0.32 | |
| 0.29 |
| Shear Modulus, GPa | 26 | |
| 62 to 69 |
| Tensile Strength: Ultimate (UTS), MPa | 460 | |
| 860 to 1800 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 560 to 1460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 380 | |
| 280 |
| Melting Completion (Liquidus), °C | 630 | |
| 1380 |
| Melting Onset (Solidus), °C | 510 | |
| 1340 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 490 |
| Thermal Conductivity, W/m-K | 150 | |
| 42 |
| Thermal Expansion, µm/m-K | 24 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 2.9 |
| Density, g/cm3 | 2.9 | |
| 7.5 |
| Embodied Carbon, kg CO2/kg material | 8.3 | |
| 1.8 |
| Embodied Energy, MJ/kg | 150 | |
| 25 |
| Embodied Water, L/kg | 1140 | |
| 48 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 41 | |
| 19 to 95 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1110 | |
| 880 to 3970 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 47 | |
| 25 |
| Strength to Weight: Axial, points | 44 | |
| 32 to 66 |
| Strength to Weight: Bending, points | 45 | |
| 27 to 44 |
| Thermal Diffusivity, mm2/s | 59 | |
| 11 |
| Thermal Shock Resistance, points | 20 | |
| 25 to 53 |
Alloy Composition
| Aluminum (Al), % | 90.7 to 93.7 | |
| 0 to 0.050 |
| Arsenic (As), % | 0 | |
| 0 to 0.020 |
| Carbon (C), % | 0 | |
| 3.4 to 3.8 |
| Chromium (Cr), % | 0 to 0.050 | |
| 0 to 0.1 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 to 0.8 |
| Iron (Fe), % | 0 to 0.4 | |
| 89.6 to 94 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 0 to 0.040 |
| Manganese (Mn), % | 0 to 0.1 | |
| 0.3 to 0.4 |
| Molybdenum (Mo), % | 0 | |
| 0 to 0.3 |
| Nickel (Ni), % | 0 | |
| 0 to 2.0 |
| Phosphorus (P), % | 0 | |
| 0 to 0.040 |
| Selenium (Se), % | 0 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 0.25 | |
| 2.3 to 2.7 |
| Sulfur (S), % | 0 | |
| 0 to 0.020 |
| Tin (Sn), % | 0 | |
| 0 to 0.020 |
| Titanium (Ti), % | 0 to 0.1 | |
| 0 |
| Vanadium (V), % | 0 | |
| 0 to 0.1 |
| Zinc (Zn), % | 5.0 to 6.0 | |
| 0 |
| Zirconium (Zr), % | 0.080 to 0.18 | |
| 0 |
| Residuals, % | 0 to 0.15 | |
| 0 |