Annealed Cast R30075 Alloy
Annealed R30075 cobalt is R30075 cobalt in the annealed condition. It has the lowest strength compared to the other variants of R30075 cobalt. The graph bars on the material properties cards below compare annealed R30075 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 30 x 106 psi
Elongation at Break
12 %
Fatigue Strength
260 MPa 38 x 103 psi
Poisson's Ratio
0.29
Reduction in Area
20 %
Shear Modulus
82 GPa 12 x 106 psi
Tensile Strength: Ultimate (UTS)
780 MPa 110 x 103 psi
Tensile Strength: Yield (Proof)
480 MPa 70 x 103 psi
Thermal Properties
Latent Heat of Fusion
320 J/g
Melting Completion (Liquidus)
1360 °C 2480 °F
Melting Onset (Solidus)
1290 °C 2360 °F
Specific Heat Capacity
450 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
13 W/m-K 7.6 BTU/h-ft-°F
Thermal Expansion
12 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.1 % IACS
Otherwise Unclassified Properties
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
530 L/kg 63 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
84 MJ/m3
Resilience: Unit (Modulus of Resilience)
560 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
26 points
Strength to Weight: Bending
22 points
Thermal Diffusivity
3.5 mm2/s
Thermal Shock Resistance
21 points
Alloy Composition
| Co | 58.7 to 68 | |
| Cr | 27 to 30 | |
| Mo | 5.0 to 7.0 | |
| Mn | 0 to 1.0 | |
| Si | 0 to 1.0 | |
| Fe | 0 to 0.75 | |
| Ni | 0 to 0.5 | |
| C | 0 to 0.35 | |
| N | 0 to 0.25 | |
| W | 0 to 0.2 | |
| Al | 0 to 0.1 | |
| Ti | 0 to 0.1 | |
| P | 0 to 0.020 | |
| S | 0 to 0.010 | |
| B | 0 to 0.010 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Further Reading
ASTM F75: Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075)
ISO 5832-4: Implants for Surgery - Metallic Materials - Part 4: Cobalt-Chromium-Molybdenum Casting Alloy