SAE-AISI S7 Steel vs. SAE-AISI O7 Steel
Both SAE-AISI S7 steel and SAE-AISI O7 steel are iron alloys. They have a very high 96% of their average alloy composition in common.
For each property being compared, the top bar is SAE-AISI S7 steel and the bottom bar is SAE-AISI O7 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 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 670 to 2030 | |
| 680 to 2110 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 250 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1480 |
| Melting Onset (Solidus), °C | 1420 | |
| 1430 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 40 | |
| 41 |
| Thermal Expansion, µm/m-K | 12 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.8 | |
| 7.6 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 9.0 | |
| 8.7 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 5.0 | |
| 6.0 |
| Density, g/cm3 | 7.8 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 2.3 | |
| 2.3 |
| Embodied Energy, MJ/kg | 31 | |
| 33 |
| Embodied Water, L/kg | 65 | |
| 52 |
Common Calculations
| PREN (Pitting Resistance) | 8.4 | |
| 3.6 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 24 |
| Strength to Weight: Axial, points | 24 to 72 | |
| 24 to 74 |
| Strength to Weight: Bending, points | 22 to 46 | |
| 22 to 46 |
| Thermal Diffusivity, mm2/s | 11 | |
| 11 |
| Thermal Shock Resistance, points | 22 to 66 | |
| 23 to 70 |
Alloy Composition
| Carbon (C), % | 0.45 to 0.55 | |
| 1.1 to 1.3 |
| Chromium (Cr), % | 3.0 to 3.5 | |
| 0.35 to 0.85 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 to 0.25 |
| Iron (Fe), % | 91.6 to 94.9 | |
| 92.9 to 97.6 |
| Manganese (Mn), % | 0.2 to 0.9 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 1.3 to 1.8 | |
| 0 to 0.3 |
| Nickel (Ni), % | 0 | |
| 0 to 0.3 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 to 0.030 |
| Silicon (Si), % | 0.2 to 1.0 | |
| 0 to 0.6 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Tungsten (W), % | 0 | |
| 1.0 to 2.0 |
| Vanadium (V), % | 0 to 0.3 | |
| 0 to 0.4 |