Grade 21 Titanium vs. R30075 Cobalt
Grade 21 titanium belongs to the titanium alloys classification, while R30075 cobalt belongs to the cobalt 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 grade 21 titanium and the bottom bar is R30075 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 140 | |
| 210 to 250 |
| Elongation at Break, % | 9.0 to 17 | |
| 12 |
| Fatigue Strength, MPa | 550 to 660 | |
| 250 to 840 |
| Poisson's Ratio | 0.32 | |
| 0.29 |
| Reduction in Area, % | 22 | |
| 20 |
| Shear Modulus, GPa | 51 | |
| 82 to 98 |
| Tensile Strength: Ultimate (UTS), MPa | 890 to 1340 | |
| 780 to 1280 |
| Tensile Strength: Yield (Proof), MPa | 870 to 1170 | |
| 480 to 840 |
Thermal Properties
| Latent Heat of Fusion, J/g | 410 | |
| 320 |
| Melting Completion (Liquidus), °C | 1740 | |
| 1360 |
| Melting Onset (Solidus), °C | 1690 | |
| 1290 |
| Specific Heat Capacity, J/kg-K | 500 | |
| 450 |
| Thermal Conductivity, W/m-K | 7.5 | |
| 13 |
| Thermal Expansion, µm/m-K | 7.1 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 5.4 | |
| 8.4 |
| Embodied Carbon, kg CO2/kg material | 32 | |
| 8.1 |
| Embodied Energy, MJ/kg | 490 | |
| 110 |
| Embodied Water, L/kg | 180 | |
| 530 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 110 to 180 | |
| 84 to 140 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 2760 to 5010 | |
| 560 to 1410 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 to 17 |
| Stiffness to Weight: Bending, points | 32 | |
| 24 to 25 |
| Strength to Weight: Axial, points | 46 to 69 | |
| 26 to 42 |
| Strength to Weight: Bending, points | 38 to 50 | |
| 22 to 31 |
| Thermal Diffusivity, mm2/s | 2.8 | |
| 3.5 |
| Thermal Shock Resistance, points | 66 to 100 | |
| 21 to 29 |
Alloy Composition
| Aluminum (Al), % | 2.5 to 3.5 | |
| 0 to 0.1 |
| Boron (B), % | 0 | |
| 0 to 0.010 |
| Carbon (C), % | 0 to 0.050 | |
| 0 to 0.35 |
| Chromium (Cr), % | 0 | |
| 27 to 30 |
| Cobalt (Co), % | 0 | |
| 58.7 to 68 |
| Hydrogen (H), % | 0 to 0.015 | |
| 0 |
| Iron (Fe), % | 0 to 0.4 | |
| 0 to 0.75 |
| Manganese (Mn), % | 0 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 14 to 16 | |
| 5.0 to 7.0 |
| Nickel (Ni), % | 0 | |
| 0 to 0.5 |
| Niobium (Nb), % | 2.2 to 3.2 | |
| 0 |
| Nitrogen (N), % | 0 to 0.030 | |
| 0 to 0.25 |
| Oxygen (O), % | 0 to 0.17 | |
| 0 |
| Phosphorus (P), % | 0 | |
| 0 to 0.020 |
| Silicon (Si), % | 0.15 to 0.25 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.010 |
| Titanium (Ti), % | 76 to 81.2 | |
| 0 to 0.1 |
| Tungsten (W), % | 0 | |
| 0 to 0.2 |
| Residuals, % | 0 to 0.4 | |
| 0 |