7021 Aluminum vs. AWS BNi-8
7021 aluminum belongs to the aluminum alloys classification, while AWS BNi-8 belongs to the nickel alloys. There are 19 material properties with values for both materials. Properties with values for just one material (12, 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 AWS BNi-8.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 69 | |
| 180 |
| Poisson's Ratio | 0.32 | |
| 0.32 |
| Shear Modulus, GPa | 26 | |
| 67 |
| Tensile Strength: Ultimate (UTS), MPa | 460 | |
| 570 |
Thermal Properties
| Latent Heat of Fusion, J/g | 380 | |
| 390 |
| Melting Completion (Liquidus), °C | 630 | |
| 1010 |
| Melting Onset (Solidus), °C | 510 | |
| 980 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 480 |
| Thermal Expansion, µm/m-K | 24 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 46 |
| Density, g/cm3 | 2.9 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 8.3 | |
| 8.2 |
| Embodied Energy, MJ/kg | 150 | |
| 120 |
| Embodied Water, L/kg | 1140 | |
| 220 |
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 12 |
| Stiffness to Weight: Bending, points | 47 | |
| 24 |
| Strength to Weight: Axial, points | 44 | |
| 20 |
| Strength to Weight: Bending, points | 45 | |
| 19 |
| Thermal Shock Resistance, points | 20 | |
| 17 |
Alloy Composition
| Aluminum (Al), % | 90.7 to 93.7 | |
| 0 to 0.050 |
| Carbon (C), % | 0 | |
| 0 to 0.060 |
| Chromium (Cr), % | 0 to 0.050 | |
| 0 |
| Cobalt (Co), % | 0 | |
| 0 to 0.1 |
| Copper (Cu), % | 0 to 0.25 | |
| 4.0 to 5.0 |
| Iron (Fe), % | 0 to 0.4 | |
| 0 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 0 |
| Manganese (Mn), % | 0 to 0.1 | |
| 21.5 to 24.5 |
| Nickel (Ni), % | 0 | |
| 61.6 to 68.5 |
| Phosphorus (P), % | 0 | |
| 0 to 0.020 |
| Selenium (Se), % | 0 | |
| 0 to 0.0050 |
| Silicon (Si), % | 0 to 0.25 | |
| 6.0 to 8.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.020 |
| Titanium (Ti), % | 0 to 0.1 | |
| 0 to 0.050 |
| Zinc (Zn), % | 5.0 to 6.0 | |
| 0 |
| Zirconium (Zr), % | 0.080 to 0.18 | |
| 0 to 0.050 |
| Residuals, % | 0 | |
| 0 to 0.5 |