Annealed R30008 Cobalt
Annealed R30008 cobalt is R30008 cobalt in the annealed condition. The graph bars on the material properties cards below compare annealed R30008 cobalt to other cobalt alloys (top) and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
210 GPa 31 x 106 psi
Elongation at Break
73 %
Fatigue Strength
320 MPa 46 x 103 psi
Poisson's Ratio
0.29
Shear Modulus
83 GPa 12 x 106 psi
Tensile Strength: Ultimate (UTS)
950 MPa 140 x 103 psi
Tensile Strength: Yield (Proof)
500 MPa 73 x 103 psi
Thermal Properties
Latent Heat of Fusion
320 J/g
Melting Completion (Liquidus)
1400 °C 2550 °F
Melting Onset (Solidus)
1330 °C 2430 °F
Specific Heat Capacity
450 J/kg-K 0.11 BTU/lb-°F
Thermal Expansion
13 µm/m-K
Otherwise Unclassified Properties
Base Metal Price
95 % relative
Density
8.4 g/cm3 530 lb/ft3
Embodied Carbon
8.1 kg CO2/kg material
Embodied Energy
110 MJ/kg 46 x 103 BTU/lb
Embodied Water
400 L/kg 48 gal/lb
Common Calculations
Resilience: Unit (Modulus of Resilience)
590 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
31 points
Strength to Weight: Bending
25 points
Thermal Shock Resistance
25 points
Alloy Composition
| Co | 39 to 42 | |
| Cr | 18.5 to 21.5 | |
| Ni | 15 to 18 | |
| Fe | 7.6 to 20 | |
| Mo | 6.5 to 7.5 | |
| Mn | 1.0 to 2.0 | |
| Si | 0 to 1.2 | |
| C | 0 to 0.15 | |
| P | 0 to 0.015 | |
| S | 0 to 0.015 | |
| B | 0 to 0.0010 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Further Reading
ASTM F1058: Standard Specification for Wrought 40Cobalt-20Chromium-16Iron-15Nickel-7Molybdenum Alloy Wire and Strip for Surgical Implant Applications (UNS R30003 and UNS R30008)
ISO 5832-7: Implants for Surgery - Metallic Materials - Part 7: Forgeable and Cold-Formed Cobalt-Chromium-Nickel-Molybdenum-Iron Alloy