7021 Aluminum vs. ASTM A732 Cast Steel
7021 aluminum belongs to the aluminum alloys classification, while ASTM A732 cast steel belongs to the iron alloys. There are 29 material properties with values for both materials. Properties with values for just one material (2, 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 ASTM A732 cast steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 69 | |
| 190 |
| Elongation at Break, % | 9.4 | |
| 4.0 to 25 |
| Fatigue Strength, MPa | 150 | |
| 230 to 750 |
| Poisson's Ratio | 0.32 | |
| 0.29 |
| Shear Modulus, GPa | 26 | |
| 72 to 73 |
| Tensile Strength: Ultimate (UTS), MPa | 460 | |
| 460 to 1470 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 310 to 1340 |
Thermal Properties
| Latent Heat of Fusion, J/g | 380 | |
| 250 to 260 |
| Maximum Temperature: Mechanical, °C | 200 | |
| 400 to 430 |
| Melting Completion (Liquidus), °C | 630 | |
| 1440 to 1460 |
| Melting Onset (Solidus), °C | 510 | |
| 1400 to 1420 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 470 to 480 |
| Thermal Conductivity, W/m-K | 150 | |
| 39 to 50 |
| Thermal Expansion, µm/m-K | 24 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 38 | |
| 7.1 to 7.7 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 120 | |
| 8.2 to 8.9 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 2.0 to 3.8 |
| Density, g/cm3 | 2.9 | |
| 7.8 to 7.9 |
| Embodied Carbon, kg CO2/kg material | 8.3 | |
| 1.4 to 1.7 |
| Embodied Energy, MJ/kg | 150 | |
| 19 to 24 |
| Embodied Water, L/kg | 1140 | |
| 47 to 54 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 41 | |
| 45 to 130 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1110 | |
| 260 to 4770 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 47 | |
| 24 |
| Strength to Weight: Axial, points | 44 | |
| 16 to 52 |
| Strength to Weight: Bending, points | 45 | |
| 17 to 37 |
| Thermal Diffusivity, mm2/s | 59 | |
| 10 to 14 |
| Thermal Shock Resistance, points | 20 | |
| 14 to 43 |