ASTM A229 Spring Steel vs. ASTM A204 Steel
Both ASTM A229 spring steel and ASTM A204 steel are iron alloys.
For each property being compared, the top bar is ASTM A229 spring steel and the bottom bar is ASTM A204 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 490 to 550 | |
| 160 to 180 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 14 | |
| 18 to 22 |
| Fatigue Strength, MPa | 710 to 790 | |
| 200 to 220 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 72 | |
| 73 |
| Shear Strength, MPa | 1020 to 1140 | |
| 330 to 360 |
| Tensile Strength: Ultimate (UTS), MPa | 1690 to 1890 | |
| 520 to 590 |
| Tensile Strength: Yield (Proof), MPa | 1100 to 1230 | |
| 290 to 330 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 410 |
| Melting Completion (Liquidus), °C | 1450 | |
| 1470 |
| Melting Onset (Solidus), °C | 1410 | |
| 1420 to 1430 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 50 | |
| 52 |
| Thermal Expansion, µm/m-K | 12 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.2 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 8.2 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 2.4 |
| Density, g/cm3 | 7.8 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.5 |
| Embodied Energy, MJ/kg | 19 | |
| 20 |
| Embodied Water, L/kg | 46 | |
| 47 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 200 to 230 | |
| 90 to 95 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 3260 to 4080 | |
| 220 to 290 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 60 to 67 | |
| 18 to 21 |
| Strength to Weight: Bending, points | 40 to 43 | |
| 18 to 20 |
| Thermal Diffusivity, mm2/s | 14 | |
| 14 |
| Thermal Shock Resistance, points | 54 to 60 | |
| 15 to 17 |