ASTM A227 Spring Steel vs. Hardened AISI 440C
Both ASTM A227 spring steel and hardened AISI 440C are iron alloys. They have 82% of their average alloy composition in common. There are 29 material properties with values for both materials. Properties with values for just one material (3, in this case) are not shown.
For each property being compared, the top bar is ASTM A227 spring steel and the bottom bar is hardened AISI 440C.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 200 |
| Elongation at Break, % | 12 | |
| 2.0 |
| Fatigue Strength, MPa | 900 to 1160 | |
| 840 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 72 | |
| 76 |
| Shear Strength, MPa | 1030 to 1330 | |
| 1120 |
| Tensile Strength: Ultimate (UTS), MPa | 1720 to 2220 | |
| 1970 |
| Tensile Strength: Yield (Proof), MPa | 1430 to 1850 | |
| 1900 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 280 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 870 |
| Melting Completion (Liquidus), °C | 1450 | |
| 1480 |
| Melting Onset (Solidus), °C | 1410 | |
| 1370 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 52 | |
| 22 |
| Thermal Expansion, µm/m-K | 12 | |
| 10 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
| 2.4 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 2.8 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 9.0 |
| Density, g/cm3 | 7.8 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 2.2 |
| Embodied Energy, MJ/kg | 19 | |
| 31 |
| Embodied Water, L/kg | 46 | |
| 120 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 200 to 260 | |
| 39 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 61 to 79 | |
| 71 |
| Strength to Weight: Bending, points | 41 to 48 | |
| 46 |
| Thermal Diffusivity, mm2/s | 14 | |
| 6.0 |
| Thermal Shock Resistance, points | 55 to 71 | |
| 71 |
Alloy Composition
| Carbon (C), % | 0.45 to 0.85 | |
| 1.0 to 1.2 |
| Chromium (Cr), % | 0 | |
| 16 to 18 |
| Iron (Fe), % | 97.4 to 99.1 | |
| 78 to 83.1 |
| Manganese (Mn), % | 0.3 to 1.3 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 0 | |
| 0 to 0.75 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.015 |