High Carbon Co-28Cr-6Mo Alloy (ASTM F1537 Alloy 2, ISO 5832-12 Alloy 2, R31538)
Cobalt Alloys
Property Overview
Density8.4g/cm³
Elastic Modulus220GPa
Tensile Strength1020 to 1360MPa
Yield Strength580 to 930MPa
Brinell HardnessUnknown
Maximum Service TemperatureUnknown
Chemical Composition
C
0.15 to 0.35%
CR
26 to 30%
NI
0 to 1.0%
MO
5.0 to 7.0%
MN
0 to 1.0%
SI
0 to 1.0%
N
0 to 0.25%
CO
58.7 to 68.9%
FE
0 to 0.75%
Mechanical
Elastic (Young's, Tensile) Modulus
220 GPa
Elongation at Break
13 to 23 %
Fatigue Strength
310 to 480 MPa
Poisson's Ratio
0.29
Reduction in Area
13 to 22 %
Shear Modulus
86 GPa
Tensile Strength: Ultimate (UTS)
1020 to 1360 MPa
Tensile Strength: Yield (Proof)
580 to 930 MPa
Hardness
Rockwell C Hardness
25 to 35
Physical
Density
8.4 g/cm 3
Thermal
Latent Heat of Fusion
320 J/g
Melting Completion (Liquidus)
1360 °C
Melting Onset (Solidus)
1290 °C
Specific Heat Capacity
450 J/kg-K
Thermal Conductivity
13 W/m-K
Thermal Diffusivity
3.5 mm 2 /s
Thermal Expansion
13 µm/m-K
Thermal Shock Resistance
25 to 33 points
Electrical
Electrical Conductivity: Equal Volume
2.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.1 % IACS
Calculated
Resilience: Ultimate (Unit Rupture Work)
140 to 200 MJ/m 3
Resilience: Unit (Modulus of Resilience)
750 to 1920 kJ/m 3
Stiffness to Weight: Axial
15 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
34 to 45 points
Strength to Weight: Bending
27 to 32 points
Environmental
Embodied Carbon
8.1 kg CO 2 /kg material
Embodied Energy
110 MJ/kg
Embodied Energy
110 MJ/kg 46 x 10 3 BTU/lb
Embodied Water
530 L/kg
Embodied Water
530 L/kg 63 gal/lb
Registered Designations & Aliases
ASTM F1537 Alloy 2High Carbon Co-28Cr-6Mo Alloy (ASTM F1537 Alloy 2, ISO 5832-12 Alloy 2, R31538)ISO 5832-12 Alloy 2R31538
Standards
ASTM F1537 ASTM F1537: Standard Specification for Wrought Cobalt-28Chromium-6Molybdenum Alloys for Surgical Implants (UNS R31537, UNS R31538, and UNS R31539)
ASTM F799 ASTM F799: Standard Specification for Cobalt-28Chromium-6Molybdenum Alloy Forgings for Surgical Implants (UNS R31537, R31538, R31539)
ASTM F799 ASTM F799: Standard Specification for Cobalt-28Chromium-6Molybdenum Alloy Forgings for Surgical Implants (UNS R31537, R31538, R31539) ASTM F1537: Standard Specification for Wrought Cobalt-28Chromium-6Molybdenum Alloys for Surgical Implants (UNS R31537, UNS R31538, and UNS R31539)