ASTM A229 Spring Steel vs. EN 1.1221 Steel
Both ASTM A229 spring steel and EN 1.1221 steel are iron alloys. Their average alloy composition is basically identical.
For each property being compared, the top bar is ASTM A229 spring steel and the bottom bar is EN 1.1221 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 490 to 550 | |
| 210 to 250 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 14 | |
| 10 to 21 |
| Fatigue Strength, MPa | 710 to 790 | |
| 240 to 340 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 72 | |
| 72 |
| Shear Strength, MPa | 1020 to 1140 | |
| 450 to 520 |
| Tensile Strength: Ultimate (UTS), MPa | 1690 to 1890 | |
| 730 to 870 |
| Tensile Strength: Yield (Proof), MPa | 1100 to 1230 | |
| 390 to 550 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 400 |
| Melting Completion (Liquidus), °C | 1450 | |
| 1460 |
| Melting Onset (Solidus), °C | 1410 | |
| 1410 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 50 | |
| 48 |
| Thermal Expansion, µm/m-K | 12 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 8.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 2.1 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.5 |
| Embodied Energy, MJ/kg | 19 | |
| 19 |
| Embodied Water, L/kg | 46 | |
| 47 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 200 to 230 | |
| 67 to 130 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 3260 to 4080 | |
| 410 to 800 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 60 to 67 | |
| 26 to 31 |
| Strength to Weight: Bending, points | 40 to 43 | |
| 23 to 26 |
| Thermal Diffusivity, mm2/s | 14 | |
| 13 |
| Thermal Shock Resistance, points | 54 to 60 | |
| 23 to 28 |
Alloy Composition
| Carbon (C), % | 0.55 to 0.85 | |
| 0.57 to 0.65 |
| Chromium (Cr), % | 0 | |
| 0 to 0.4 |
| Iron (Fe), % | 97.5 to 99 | |
| 97.1 to 98.8 |
| Manganese (Mn), % | 0.3 to 1.2 | |
| 0.6 to 0.9 |
| Molybdenum (Mo), % | 0 | |
| 0 to 0.1 |
| Nickel (Ni), % | 0 | |
| 0 to 0.4 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.035 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 0.4 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.035 |