SAE-AISI 1140 Steel vs. ASTM A229 Spring Steel
Both SAE-AISI 1140 steel and ASTM A229 spring steel are iron alloys. Their average alloy composition is basically identical. There are 31 material properties with values for both materials. Properties with values for just one material (1, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 1140 steel and the bottom bar is ASTM A229 spring steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 to 180 | |
| 490 to 550 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 14 to 18 | |
| 14 |
| Fatigue Strength, MPa | 230 to 370 | |
| 710 to 790 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 72 | |
| 72 |
| Shear Strength, MPa | 370 to 420 | |
| 1020 to 1140 |
| Tensile Strength: Ultimate (UTS), MPa | 600 to 700 | |
| 1690 to 1890 |
| Tensile Strength: Yield (Proof), MPa | 340 to 570 | |
| 1100 to 1230 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 400 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1450 |
| Melting Onset (Solidus), °C | 1420 | |
| 1410 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 51 | |
| 50 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.0 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.1 | |
| 8.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 1.8 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.4 |
| Embodied Energy, MJ/kg | 18 | |
| 19 |
| Embodied Water, L/kg | 46 | |
| 46 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 89 to 93 | |
| 200 to 230 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 310 to 870 | |
| 3260 to 4080 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 21 to 25 | |
| 60 to 67 |
| Strength to Weight: Bending, points | 20 to 22 | |
| 40 to 43 |
| Thermal Diffusivity, mm2/s | 14 | |
| 14 |
| Thermal Shock Resistance, points | 18 to 21 | |
| 54 to 60 |
Alloy Composition
| Carbon (C), % | 0.37 to 0.44 | |
| 0.55 to 0.85 |
| Iron (Fe), % | 98.4 to 98.9 | |
| 97.5 to 99 |
| Manganese (Mn), % | 0.7 to 1.0 | |
| 0.3 to 1.2 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0.080 to 0.13 | |
| 0 to 0.050 |