R30003 Cobalt vs. ASTM A227 Spring Steel
R30003 cobalt belongs to the cobalt alloys classification, while ASTM A227 spring steel belongs to the iron alloys. There are 26 material properties with values for both materials. Properties with values for just one material (5, in this case) are not shown.
For each property being compared, the top bar is R30003 cobalt and the bottom bar is ASTM A227 spring steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 10 to 73 | |
| 12 |
| Fatigue Strength, MPa | 320 to 560 | |
| 900 to 1160 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 83 | |
| 72 |
| Tensile Strength: Ultimate (UTS), MPa | 970 to 1720 | |
| 1720 to 2220 |
| Tensile Strength: Yield (Proof), MPa | 510 to 1090 | |
| 1430 to 1850 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 250 |
| Melting Completion (Liquidus), °C | 1400 | |
| 1450 |
| Melting Onset (Solidus), °C | 1440 | |
| 1410 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 470 |
| Thermal Conductivity, W/m-K | 13 | |
| 52 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.0 | |
| 7.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.1 | |
| 8.3 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 95 | |
| 1.8 |
| Density, g/cm3 | 8.4 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 1.4 |
| Embodied Energy, MJ/kg | 110 | |
| 19 |
| Embodied Water, L/kg | 400 | |
| 46 |
Common Calculations
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 32 to 57 | |
| 61 to 79 |
| Strength to Weight: Bending, points | 26 to 38 | |
| 41 to 48 |
| Thermal Diffusivity, mm2/s | 3.3 | |
| 14 |
| Thermal Shock Resistance, points | 26 to 45 | |
| 55 to 71 |
Alloy Composition
| Boron (B), % | 0 to 0.1 | |
| 0 |
| Carbon (C), % | 0 to 0.15 | |
| 0.45 to 0.85 |
| Chromium (Cr), % | 19 to 21 | |
| 0 |
| Cobalt (Co), % | 39 to 41 | |
| 0 |
| Iron (Fe), % | 10 to 20.5 | |
| 97.4 to 99.1 |
| Manganese (Mn), % | 1.5 to 2.5 | |
| 0.3 to 1.3 |
| Molybdenum (Mo), % | 6.0 to 8.0 | |
| 0 |
| Nickel (Ni), % | 14 to 16 | |
| 0 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.2 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.050 |