R31538 Cobalt vs. Grade N7M Nickel

R31538 cobalt belongs to the cobalt alloys classification, while grade N7M nickel belongs to the nickel alloys. There are 23 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.

For each property being compared, the top bar is R31538 cobalt and the bottom bar is grade N7M nickel.

High Carbon Co-28Cr-6Mo Alloy (ASTM F1537 Alloy 2, ISO 5832-12 Alloy 2, R31538)Grade N7M (J30007) Cast Nickel

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		220
Elastic (Young's, Tensile) Modulus, GPa		220

Elongation at Break, %		13 to 23
Elongation at Break, %		22

Fatigue Strength, MPa		310 to 480
Fatigue Strength, MPa		190

Poisson's Ratio		0.29
Poisson's Ratio		0.31

Shear Modulus, GPa		86
Shear Modulus, GPa		85

Tensile Strength: Ultimate (UTS), MPa		1020 to 1360
Tensile Strength: Ultimate (UTS), MPa		590

Tensile Strength: Yield (Proof), MPa		580 to 930
Tensile Strength: Yield (Proof), MPa		310

Thermal Properties

Latent Heat of Fusion, J/g		320
Latent Heat of Fusion, J/g		320

Melting Completion (Liquidus), °C		1360
Melting Completion (Liquidus), °C		1650

Melting Onset (Solidus), °C		1290
Melting Onset (Solidus), °C		1590

Specific Heat Capacity, J/kg-K		450
Specific Heat Capacity, J/kg-K		390

Thermal Expansion, µm/m-K		13
Thermal Expansion, µm/m-K		9.9

Otherwise Unclassified Properties

Density, g/cm³		8.4
Density, g/cm³		9.3

Embodied Carbon, kg CO₂/kg material		8.1
Embodied Carbon, kg CO₂/kg material		16

Embodied Energy, MJ/kg		110
Embodied Energy, MJ/kg		200

Embodied Water, L/kg		530
Embodied Water, L/kg		270

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m³		140 to 200
Resilience: Ultimate (Unit Rupture Work), MJ/m³		110

Resilience: Unit (Modulus of Resilience), kJ/m³		750 to 1920
Resilience: Unit (Modulus of Resilience), kJ/m³		220

Stiffness to Weight: Axial, points		15
Stiffness to Weight: Axial, points		13

Stiffness to Weight: Bending, points		24
Stiffness to Weight: Bending, points		22

Strength to Weight: Axial, points		34 to 45
Strength to Weight: Axial, points		18

Strength to Weight: Bending, points		27 to 32
Strength to Weight: Bending, points		17

Thermal Shock Resistance, points		25 to 33
Thermal Shock Resistance, points		19

Alloy Composition

Carbon (C), %		0.15 to 0.35
Carbon (C), %		0 to 0.070

Chromium (Cr), %		26 to 30
Chromium (Cr), %		0 to 1.0

Cobalt (Co), %		58.7 to 68.9
Cobalt (Co), %		0

Iron (Fe), %		0 to 0.75
Iron (Fe), %		0 to 3.0

Manganese (Mn), %		0 to 1.0
Manganese (Mn), %		0 to 1.0

Molybdenum (Mo), %		5.0 to 7.0
Molybdenum (Mo), %		30 to 33

Nickel (Ni), %		0 to 1.0
Nickel (Ni), %		60.9 to 70

Nitrogen (N), %		0 to 0.25
Nitrogen (N), %		0

Phosphorus (P), %		0
Phosphorus (P), %		0 to 0.040

Silicon (Si), %		0 to 1.0
Silicon (Si), %		0 to 1.0

Sulfur (S), %		0
Sulfur (S), %		0 to 0.030