UNS R30075 (ASTM F75, ISO 5832-4) Co-Cr-Mo Alloy

R30075 cobalt is a cobalt alloy. ASTM F75 is the defining standard for this material. R30075 is the UNS number.

The properties of R30075 cobalt include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare 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.

Annealed Cast R30075 Alloy Heat Treated Cast R30075 Alloy

Pressure Sintered (Hot Pressed) R30075 Alloy

Mechanical Properties

Elastic (Young's, Tensile) Modulus

210 to 250 GPa 30 to 36 x 10⁶ psi

Elongation at Break

12 %

Fatigue Strength

250 to 840 MPa 37 to 120 x 10³ psi

Poisson's Ratio

0.29

Reduction in Area

20 %

Shear Modulus

82 to 98 GPa 12 to 14 x 10⁶ psi

Tensile Strength: Ultimate (UTS)

780 to 1280 MPa 110 to 190 x 10³ psi

Tensile Strength: Yield (Proof)

480 to 840 MPa 70 to 120 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 to 140 MJ/m³

Resilience: Unit (Modulus of Resilience)

560 to 1410 kJ/m³

Stiffness to Weight: Axial

14 to 17 points

Stiffness to Weight: Bending

24 to 25 points

Strength to Weight: Axial

26 to 42 points

Strength to Weight: Bending

22 to 31 points

Thermal Diffusivity

3.5 mm²/s

Thermal Shock Resistance

21 to 29 points

Alloy Composition

Cobalt (Co)Co		58.7 to 68
Chromium (Cr)Cr		27 to 30
Molybdenum (Mo)Mo		5.0 to 7.0
Manganese (Mn)Mn		0 to 1.0
Silicon (Si)Si		0 to 1.0
Iron (Fe)Fe		0 to 0.75
Nickel (Ni)Ni		0 to 0.5
Carbon (C)C		0 to 0.35
Nitrogen (N)N		0 to 0.25
Tungsten (W)W		0 to 0.2
Aluminum (Al)Al		0 to 0.1
Titanium (Ti)Ti		0 to 0.1
Phosphorus (P)P		0 to 0.020
Sulfur (S)S		0 to 0.010
Boron (B)B		0 to 0.010