2218 Aluminum vs. ASTM A204 Steel
2218 aluminum belongs to the aluminum alloys classification, while ASTM A204 steel belongs to the iron alloys. 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 2218 aluminum and the bottom bar is ASTM A204 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 95 to 110 | |
| 160 to 180 |
| Elastic (Young's, Tensile) Modulus, GPa | 73 | |
| 190 |
| Elongation at Break, % | 6.8 to 10 | |
| 18 to 22 |
| Fatigue Strength, MPa | 110 | |
| 200 to 220 |
| Poisson's Ratio | 0.33 | |
| 0.29 |
| Shear Modulus, GPa | 27 | |
| 73 |
| Shear Strength, MPa | 210 to 250 | |
| 330 to 360 |
| Tensile Strength: Ultimate (UTS), MPa | 330 to 430 | |
| 520 to 590 |
| Tensile Strength: Yield (Proof), MPa | 260 to 310 | |
| 290 to 330 |
Thermal Properties
| Latent Heat of Fusion, J/g | 390 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 220 | |
| 410 |
| Melting Completion (Liquidus), °C | 640 | |
| 1470 |
| Melting Onset (Solidus), °C | 510 | |
| 1420 to 1430 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 470 |
| Thermal Conductivity, W/m-K | 140 | |
| 52 |
| Thermal Expansion, µm/m-K | 22 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 37 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 110 | |
| 8.2 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 11 | |
| 2.4 |
| Density, g/cm3 | 3.1 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 8.2 | |
| 1.5 |
| Embodied Energy, MJ/kg | 150 | |
| 20 |
| Embodied Water, L/kg | 1130 | |
| 47 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 27 to 31 | |
| 90 to 95 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 450 to 650 | |
| 220 to 290 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 45 | |
| 24 |
| Strength to Weight: Axial, points | 30 to 39 | |
| 18 to 21 |
| Strength to Weight: Bending, points | 34 to 41 | |
| 18 to 20 |
| Thermal Diffusivity, mm2/s | 52 | |
| 14 |
| Thermal Shock Resistance, points | 15 to 19 | |
| 15 to 17 |