SAE-AISI O7 Steel vs. ASTM A229 Spring Steel
Both SAE-AISI O7 steel and ASTM A229 spring steel are iron alloys. They have a very high 97% 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 SAE-AISI O7 steel and the bottom bar is ASTM A229 spring 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 | 73 | |
| 72 |
| Tensile Strength: Ultimate (UTS), MPa | 680 to 2110 | |
| 1690 to 1890 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Melting Completion (Liquidus), °C | 1480 | |
| 1450 |
| Melting Onset (Solidus), °C | 1430 | |
| 1410 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 41 | |
| 50 |
| Thermal Expansion, µm/m-K | 12 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.6 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.7 | |
| 8.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 6.0 | |
| 1.8 |
| Density, g/cm3 | 7.9 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 2.3 | |
| 1.4 |
| Embodied Energy, MJ/kg | 33 | |
| 19 |
| Embodied Water, L/kg | 52 | |
| 46 |
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 24 to 74 | |
| 60 to 67 |
| Strength to Weight: Bending, points | 22 to 46 | |
| 40 to 43 |
| Thermal Diffusivity, mm2/s | 11 | |
| 14 |
| Thermal Shock Resistance, points | 23 to 70 | |
| 54 to 60 |
Alloy Composition
| Carbon (C), % | 1.1 to 1.3 | |
| 0.55 to 0.85 |
| Chromium (Cr), % | 0.35 to 0.85 | |
| 0 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 |
| Iron (Fe), % | 92.9 to 97.6 | |
| 97.5 to 99 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0.3 to 1.2 |
| Molybdenum (Mo), % | 0 to 0.3 | |
| 0 |
| Nickel (Ni), % | 0 to 0.3 | |
| 0 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.6 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.050 |
| Tungsten (W), % | 1.0 to 2.0 | |
| 0 |
| Vanadium (V), % | 0 to 0.4 | |
| 0 |