SAE-AISI 1090 Steel vs. ASTM A387 Grade 21 Steel
Both SAE-AISI 1090 steel and ASTM A387 grade 21 steel are iron alloys. They have a very high 96% of their average alloy composition in common. There are 31 material properties with values for both materials. Properties with values for just one material (2, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 1090 steel and the bottom bar is ASTM A387 grade 21 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 220 to 280 | |
| 150 to 180 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 11 | |
| 21 |
| Fatigue Strength, MPa | 320 to 380 | |
| 160 to 250 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 72 | |
| 74 |
| Shear Strength, MPa | 470 to 570 | |
| 310 to 370 |
| Tensile Strength: Ultimate (UTS), MPa | 790 to 950 | |
| 500 to 590 |
| Tensile Strength: Yield (Proof), MPa | 520 to 610 | |
| 230 to 350 |
Thermal Properties
| Latent Heat of Fusion, J/g | 240 | |
| 260 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 480 |
| Melting Completion (Liquidus), °C | 1450 | |
| 1470 |
| Melting Onset (Solidus), °C | 1410 | |
| 1430 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 50 | |
| 41 |
| Thermal Expansion, µm/m-K | 12 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.1 | |
| 7.6 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.2 | |
| 8.8 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 4.1 |
| Density, g/cm3 | 7.8 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.8 |
| Embodied Energy, MJ/kg | 19 | |
| 23 |
| Embodied Water, L/kg | 46 | |
| 62 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 82 to 91 | |
| 84 to 110 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 730 to 1000 | |
| 140 to 320 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 28 to 34 | |
| 18 to 21 |
| Strength to Weight: Bending, points | 24 to 27 | |
| 18 to 20 |
| Thermal Diffusivity, mm2/s | 13 | |
| 11 |
| Thermal Shock Resistance, points | 25 to 31 | |
| 14 to 17 |
Alloy Composition
| Carbon (C), % | 0.85 to 1.0 | |
| 0.050 to 0.15 |
| Chromium (Cr), % | 0 | |
| 2.8 to 3.3 |
| Iron (Fe), % | 98 to 98.6 | |
| 94.4 to 96 |
| Manganese (Mn), % | 0.6 to 0.9 | |
| 0.3 to 0.6 |
| Molybdenum (Mo), % | 0 | |
| 0.9 to 1.1 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.025 |
| Silicon (Si), % | 0 | |
| 0 to 0.5 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.025 |