ASTM A387 Grade 21 Steel vs. SAE-AISI S4 Steel
Both ASTM A387 grade 21 steel and SAE-AISI S4 steel are iron alloys. They have a very high 96% of their average alloy composition in common. There are 23 material properties with values for both materials. Properties with values for just one material (9, in this case) are not shown.
For each property being compared, the top bar is ASTM A387 grade 21 steel and the bottom bar is SAE-AISI S4 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 74 | |
| 72 |
| Tensile Strength: Ultimate (UTS), MPa | 500 to 590 | |
| 670 to 2140 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 280 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1430 |
| Melting Onset (Solidus), °C | 1430 | |
| 1390 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 41 | |
| 44 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 7.4 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 | |
| 8.7 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 4.1 | |
| 2.2 |
| Density, g/cm3 | 7.9 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 2.0 |
| Embodied Energy, MJ/kg | 23 | |
| 29 |
| Embodied Water, L/kg | 62 | |
| 48 |
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 18 to 21 | |
| 24 to 77 |
| Strength to Weight: Bending, points | 18 to 20 | |
| 22 to 48 |
| Thermal Diffusivity, mm2/s | 11 | |
| 12 |
| Thermal Shock Resistance, points | 14 to 17 | |
| 20 to 65 |
Alloy Composition
| Carbon (C), % | 0.050 to 0.15 | |
| 0.5 to 0.65 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 0.1 to 0.5 |
| Iron (Fe), % | 94.4 to 96 | |
| 95.2 to 96.9 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0.6 to 1.0 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 0 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 0.5 | |
| 1.8 to 2.3 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 to 0.030 |
| Vanadium (V), % | 0 | |
| 0.15 to 0.35 |