EN 1.7221 Steel vs. SAE-AISI 8740 Steel
Both EN 1.7221 steel and SAE-AISI 8740 steel are iron alloys. Their average alloy composition is basically identical. There are 30 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 EN 1.7221 steel and the bottom bar is SAE-AISI 8740 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 to 230 | |
| 170 to 200 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 11 to 17 | |
| 11 to 23 |
| Fatigue Strength, MPa | 290 to 390 | |
| 270 to 350 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 650 to 780 | |
| 580 to 670 |
| Tensile Strength: Yield (Proof), MPa | 430 to 630 | |
| 380 to 570 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 420 | |
| 410 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1460 |
| Melting Onset (Solidus), °C | 1420 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 44 | |
| 39 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
| 7.3 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
| 8.4 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.4 | |
| 2.6 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.5 | |
| 1.5 |
| Embodied Energy, MJ/kg | 20 | |
| 20 |
| Embodied Water, L/kg | 51 | |
| 50 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 83 to 98 | |
| 71 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 490 to 1050 | |
| 390 to 850 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 23 to 27 | |
| 20 to 24 |
| Strength to Weight: Bending, points | 21 to 24 | |
| 20 to 22 |
| Thermal Diffusivity, mm2/s | 12 | |
| 10 |
| Thermal Shock Resistance, points | 19 to 23 | |
| 17 to 20 |
Alloy Composition
| Carbon (C), % | 0.22 to 0.29 | |
| 0.38 to 0.43 |
| Chromium (Cr), % | 0.8 to 1.2 | |
| 0.4 to 0.6 |
| Iron (Fe), % | 96.8 to 98.3 | |
| 96.5 to 97.7 |
| Manganese (Mn), % | 0.5 to 0.8 | |
| 0.75 to 1.0 |
| Molybdenum (Mo), % | 0.15 to 0.3 | |
| 0.2 to 0.3 |
| Nickel (Ni), % | 0 | |
| 0.4 to 0.7 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 0.6 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.040 |