7021 Aluminum vs. 7178 Aluminum
Both 7021 aluminum and 7178 aluminum are aluminum alloys. They have a very high 95% of their average alloy composition in common.
For each property being compared, the top bar is 7021 aluminum and the bottom bar is 7178 aluminum.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 69 | |
| 71 |
| Elongation at Break, % | 9.4 | |
| 4.5 to 12 |
| Fatigue Strength, MPa | 150 | |
| 120 to 210 |
| Poisson's Ratio | 0.32 | |
| 0.32 |
| Shear Modulus, GPa | 26 | |
| 27 |
| Shear Strength, MPa | 270 | |
| 140 to 380 |
| Tensile Strength: Ultimate (UTS), MPa | 460 | |
| 240 to 640 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 120 to 560 |
Thermal Properties
| Latent Heat of Fusion, J/g | 380 | |
| 370 |
| Maximum Temperature: Mechanical, °C | 200 | |
| 180 |
| Melting Completion (Liquidus), °C | 630 | |
| 630 |
| Melting Onset (Solidus), °C | 510 | |
| 480 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 860 |
| Thermal Conductivity, W/m-K | 150 | |
| 130 |
| Thermal Expansion, µm/m-K | 24 | |
| 23 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 38 | |
| 31 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 120 | |
| 91 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.5 | |
| 10 |
| Density, g/cm3 | 2.9 | |
| 3.1 |
| Embodied Carbon, kg CO2/kg material | 8.3 | |
| 8.2 |
| Embodied Energy, MJ/kg | 150 | |
| 150 |
| Embodied Water, L/kg | 1140 | |
| 1110 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 41 | |
| 24 to 52 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1110 | |
| 110 to 2220 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 47 | |
| 45 |
| Strength to Weight: Axial, points | 44 | |
| 21 to 58 |
| Strength to Weight: Bending, points | 45 | |
| 28 to 54 |
| Thermal Diffusivity, mm2/s | 59 | |
| 47 |
| Thermal Shock Resistance, points | 20 | |
| 10 to 28 |
Alloy Composition
| Aluminum (Al), % | 90.7 to 93.7 | |
| 85.4 to 89.5 |
| Chromium (Cr), % | 0 to 0.050 | |
| 0.18 to 0.28 |
| Copper (Cu), % | 0 to 0.25 | |
| 1.6 to 2.4 |
| Iron (Fe), % | 0 to 0.4 | |
| 0 to 0.5 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 2.4 to 3.1 |
| Manganese (Mn), % | 0 to 0.1 | |
| 0 to 0.3 |
| Silicon (Si), % | 0 to 0.25 | |
| 0 to 0.4 |
| Titanium (Ti), % | 0 to 0.1 | |
| 0 to 0.2 |
| Zinc (Zn), % | 5.0 to 6.0 | |
| 6.3 to 7.3 |
| Zirconium (Zr), % | 0.080 to 0.18 | |
| 0 |
| Residuals, % | 0 | |
| 0 to 0.15 |