R30816 Cobalt vs. AISI 420 Stainless Steel
R30816 cobalt belongs to the cobalt alloys classification, while AISI 420 stainless steel belongs to the iron alloys. There are 26 material properties with values for both materials. Properties with values for just one material (9, in this case) are not shown.
For each property being compared, the top bar is R30816 cobalt and the bottom bar is AISI 420 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 280 | |
| 190 |
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 23 | |
| 8.0 to 15 |
| Fatigue Strength, MPa | 250 | |
| 220 to 670 |
| Poisson's Ratio | 0.3 | |
| 0.28 |
| Shear Modulus, GPa | 81 | |
| 76 |
| Tensile Strength: Ultimate (UTS), MPa | 1020 | |
| 690 to 1720 |
| Tensile Strength: Yield (Proof), MPa | 460 | |
| 380 to 1310 |
Thermal Properties
| Latent Heat of Fusion, J/g | 300 | |
| 280 |
| Melting Completion (Liquidus), °C | 1540 | |
| 1510 |
| Melting Onset (Solidus), °C | 1460 | |
| 1450 |
| Specific Heat Capacity, J/kg-K | 420 | |
| 480 |
| Thermal Conductivity, W/m-K | 13 | |
| 27 |
| Thermal Expansion, µm/m-K | 12 | |
| 10 |
Otherwise Unclassified Properties
| Density, g/cm3 | 9.1 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 20 | |
| 2.0 |
| Embodied Energy, MJ/kg | 320 | |
| 28 |
| Embodied Water, L/kg | 440 | |
| 100 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 190 | |
| 88 to 130 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 510 | |
| 380 to 4410 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 22 | |
| 25 |
| Strength to Weight: Axial, points | 31 | |
| 25 to 62 |
| Strength to Weight: Bending, points | 25 | |
| 22 to 41 |
| Thermal Diffusivity, mm2/s | 3.3 | |
| 7.3 |
| Thermal Shock Resistance, points | 28 | |
| 25 to 62 |
Alloy Composition
| Carbon (C), % | 0.32 to 0.42 | |
| 0.15 to 0.4 |
| Chromium (Cr), % | 19 to 21 | |
| 12 to 14 |
| Cobalt (Co), % | 40 to 49.8 | |
| 0 |
| Iron (Fe), % | 0 to 5.0 | |
| 82.3 to 87.9 |
| Manganese (Mn), % | 1.0 to 2.0 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 3.5 to 4.5 | |
| 0 to 0.5 |
| Nickel (Ni), % | 19 to 21 | |
| 0 to 0.75 |
| Niobium (Nb), % | 3.5 to 4.5 | |
| 0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 3.5 to 4.5 | |
| 0 |
| Tungsten (W), % | 3.5 to 4.5 | |
| 0 |