2218 Aluminum vs. S15500 Stainless Steel
2218 aluminum belongs to the aluminum alloys classification, while S15500 stainless steel belongs to the iron alloys. There are 31 material properties with values for both materials. Properties with values for just one material (5, 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 2218 aluminum and the bottom bar is S15500 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 95 to 110 | |
| 290 to 430 |
| Elastic (Young's, Tensile) Modulus, GPa | 73 | |
| 190 |
| Elongation at Break, % | 6.8 to 10 | |
| 6.8 to 16 |
| Fatigue Strength, MPa | 110 | |
| 350 to 650 |
| Poisson's Ratio | 0.33 | |
| 0.28 |
| Shear Modulus, GPa | 27 | |
| 75 |
| Shear Strength, MPa | 210 to 250 | |
| 540 to 870 |
| Tensile Strength: Ultimate (UTS), MPa | 330 to 430 | |
| 890 to 1490 |
| Tensile Strength: Yield (Proof), MPa | 260 to 310 | |
| 590 to 1310 |
Thermal Properties
| Latent Heat of Fusion, J/g | 390 | |
| 280 |
| Maximum Temperature: Mechanical, °C | 220 | |
| 820 |
| Melting Completion (Liquidus), °C | 640 | |
| 1430 |
| Melting Onset (Solidus), °C | 510 | |
| 1380 |
| Specific Heat Capacity, J/kg-K | 870 | |
| 480 |
| Thermal Conductivity, W/m-K | 140 | |
| 17 |
| Thermal Expansion, µm/m-K | 22 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 37 | |
| 2.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 110 | |
| 2.5 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 11 | |
| 13 |
| Density, g/cm3 | 3.1 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 8.2 | |
| 2.7 |
| Embodied Energy, MJ/kg | 150 | |
| 39 |
| Embodied Water, L/kg | 1130 | |
| 130 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 27 to 31 | |
| 98 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 450 to 650 | |
| 890 to 4460 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 45 | |
| 25 |
| Strength to Weight: Axial, points | 30 to 39 | |
| 32 to 53 |
| Strength to Weight: Bending, points | 34 to 41 | |
| 26 to 37 |
| Thermal Diffusivity, mm2/s | 52 | |
| 4.6 |
| Thermal Shock Resistance, points | 15 to 19 | |
| 30 to 50 |
Alloy Composition
| Aluminum (Al), % | 88.8 to 93.6 | |
| 0 |
| Carbon (C), % | 0 | |
| 0 to 0.070 |
| Chromium (Cr), % | 0 to 0.1 | |
| 14 to 15.5 |
| Copper (Cu), % | 3.5 to 4.5 | |
| 2.5 to 4.5 |
| Iron (Fe), % | 0 to 1.0 | |
| 71.9 to 79.9 |
| Magnesium (Mg), % | 1.2 to 1.8 | |
| 0 |
| Manganese (Mn), % | 0 to 0.2 | |
| 0 to 1.0 |
| Nickel (Ni), % | 1.7 to 2.3 | |
| 3.5 to 5.5 |
| Niobium (Nb), % | 0 | |
| 0.15 to 0.45 |
| Phosphorus (P), % | 0 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.9 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Zinc (Zn), % | 0 to 0.25 | |
| 0 |
| Residuals, % | 0 to 0.15 | |
| 0 |