SAE-AISI 5140 Steel vs. ASTM A231 Spring Steel
Both SAE-AISI 5140 steel and ASTM A231 spring 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 SAE-AISI 5140 steel and the bottom bar is ASTM A231 spring steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 to 290 | |
| 540 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 12 to 29 | |
| 14 |
| Fatigue Strength, MPa | 220 to 570 | |
| 1000 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 73 |
| Shear Strength, MPa | 360 to 600 | |
| 1080 |
| Tensile Strength: Ultimate (UTS), MPa | 560 to 970 | |
| 1790 |
| Tensile Strength: Yield (Proof), MPa | 290 to 840 | |
| 1570 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 420 | |
| 420 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1460 |
| Melting Onset (Solidus), °C | 1420 | |
| 1410 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 45 | |
| 52 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
| 7.3 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 8.4 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.1 | |
| 2.3 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 2.0 |
| Embodied Energy, MJ/kg | 19 | |
| 28 |
| Embodied Water, L/kg | 49 | |
| 51 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 76 to 180 | |
| 230 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 20 to 34 | |
| 64 |
| Strength to Weight: Bending, points | 19 to 28 | |
| 42 |
| Thermal Diffusivity, mm2/s | 12 | |
| 14 |
| Thermal Shock Resistance, points | 16 to 29 | |
| 53 |
Alloy Composition
| Carbon (C), % | 0.38 to 0.43 | |
| 0.48 to 0.53 |
| Chromium (Cr), % | 0.7 to 0.9 | |
| 0.8 to 1.1 |
| Iron (Fe), % | 97.3 to 98.1 | |
| 96.7 to 97.7 |
| Manganese (Mn), % | 0.7 to 0.9 | |
| 0.7 to 0.9 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.040 |
| Vanadium (V), % | 0 | |
| 0.15 to 0.3 |