ASTM A229 Spring Steel vs. G-CoCr28 Cobalt
ASTM A229 spring steel belongs to the iron alloys classification, while G-CoCr28 cobalt belongs to the cobalt alloys. There are 27 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is ASTM A229 spring steel and the bottom bar is G-CoCr28 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 14 | |
| 6.7 |
| Fatigue Strength, MPa | 710 to 790 | |
| 130 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 72 | |
| 83 |
| Tensile Strength: Ultimate (UTS), MPa | 1690 to 1890 | |
| 560 |
| Tensile Strength: Yield (Proof), MPa | 1100 to 1230 | |
| 260 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 320 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 1200 |
| Melting Completion (Liquidus), °C | 1450 | |
| 1330 |
| Melting Onset (Solidus), °C | 1410 | |
| 1270 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 50 | |
| 8.5 |
| Thermal Expansion, µm/m-K | 12 | |
| 14 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 100 |
| Density, g/cm3 | 7.8 | |
| 8.1 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 6.2 |
| Embodied Energy, MJ/kg | 19 | |
| 84 |
| Embodied Water, L/kg | 46 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 200 to 230 | |
| 31 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 3260 to 4080 | |
| 160 |
| Stiffness to Weight: Axial, points | 13 | |
| 15 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 60 to 67 | |
| 19 |
| Strength to Weight: Bending, points | 40 to 43 | |
| 19 |
| Thermal Diffusivity, mm2/s | 14 | |
| 2.2 |
| Thermal Shock Resistance, points | 54 to 60 | |
| 14 |
Alloy Composition
| Carbon (C), % | 0.55 to 0.85 | |
| 0.050 to 0.25 |
| Chromium (Cr), % | 0 | |
| 27 to 30 |
| Cobalt (Co), % | 0 | |
| 48 to 52 |
| Iron (Fe), % | 97.5 to 99 | |
| 9.7 to 24.5 |
| Manganese (Mn), % | 0.3 to 1.2 | |
| 0 to 1.5 |
| Molybdenum (Mo), % | 0 | |
| 0 to 0.5 |
| Nickel (Ni), % | 0 | |
| 0 to 4.0 |
| Niobium (Nb), % | 0 | |
| 0 to 0.5 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0.5 to 1.5 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.030 |