ASTM A387 Grade 21 Steel vs. 6101 Aluminum
ASTM A387 grade 21 steel belongs to the iron alloys classification, while 6101 aluminum belongs to the aluminum alloys. There are 21 material properties with values for both materials. Properties with values for just one material (11, 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 ASTM A387 grade 21 steel and the bottom bar is 6101 aluminum.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 68 |
| Elongation at Break, % | 21 | |
| 10 to 25 |
| Poisson's Ratio | 0.29 | |
| 0.33 |
| Shear Modulus, GPa | 74 | |
| 26 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 400 |
| Maximum Temperature: Mechanical, °C | 480 | |
| 160 |
| Melting Completion (Liquidus), °C | 1470 | |
| 650 |
| Melting Onset (Solidus), °C | 1430 | |
| 620 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 900 |
| Thermal Conductivity, W/m-K | 41 | |
| 220 to 230 |
| Thermal Expansion, µm/m-K | 13 | |
| 23 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 57 to 60 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 | |
| 190 to 200 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 4.1 | |
| 9.5 |
| Density, g/cm3 | 7.9 | |
| 2.7 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 8.3 |
| Embodied Energy, MJ/kg | 23 | |
| 150 |
| Embodied Water, L/kg | 62 | |
| 1190 |
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 50 |
| Thermal Diffusivity, mm2/s | 11 | |
| 89 to 93 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 97.6 to 99.4 |
| Boron (B), % | 0 | |
| 0 to 0.060 |
| Carbon (C), % | 0.050 to 0.15 | |
| 0 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 0 to 0.030 |
| Copper (Cu), % | 0 | |
| 0 to 0.1 |
| Iron (Fe), % | 94.4 to 96 | |
| 0 to 0.5 |
| Magnesium (Mg), % | 0 | |
| 0.35 to 0.8 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 to 0.030 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 0 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 |
| Silicon (Si), % | 0 to 0.5 | |
| 0.3 to 0.7 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 |
| Zinc (Zn), % | 0 | |
| 0 to 0.1 |
| Residuals, % | 0 | |
| 0 to 0.1 |