R31538 Cobalt vs. 50Cr-50Ni Alloy

R31538 cobalt belongs to the cobalt alloys classification, while 50Cr-50Ni alloy belongs to the otherwise unclassified metals. They have a modest 30% of their average alloy composition in common, which, by itself, doesn't mean much. There are 20 material properties with values for both materials. Properties with values for just one material (10, in this case) are not shown.

For each property being compared, the top bar is R31538 cobalt and the bottom bar is 50Cr-50Ni alloy.

High Carbon Co-28Cr-6Mo Alloy (ASTM F1537 Alloy 2, ISO 5832-12 Alloy 2, R31538)50Cr-50Ni (R20500) Casting Alloy

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		220
Elastic (Young's, Tensile) Modulus, GPa		210

Elongation at Break, %		13 to 23
Elongation at Break, %		5.7

Poisson's Ratio		0.29
Poisson's Ratio		0.26

Shear Modulus, GPa		86
Shear Modulus, GPa		84

Tensile Strength: Ultimate (UTS), MPa		1020 to 1360
Tensile Strength: Ultimate (UTS), MPa		620

Tensile Strength: Yield (Proof), MPa		580 to 930
Tensile Strength: Yield (Proof), MPa		390

Thermal Properties

Latent Heat of Fusion, J/g		320
Latent Heat of Fusion, J/g		350

Specific Heat Capacity, J/kg-K		450
Specific Heat Capacity, J/kg-K		490

Thermal Expansion, µm/m-K		13
Thermal Expansion, µm/m-K		15

Otherwise Unclassified Properties

Density, g/cm³		8.4
Density, g/cm³		8.0

Embodied Carbon, kg CO₂/kg material		8.1
Embodied Carbon, kg CO₂/kg material		7.9

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

Embodied Water, L/kg		530
Embodied Water, L/kg		350

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m³		140 to 200
Resilience: Ultimate (Unit Rupture Work), MJ/m³		31

Resilience: Unit (Modulus of Resilience), kJ/m³		750 to 1920
Resilience: Unit (Modulus of Resilience), kJ/m³		350

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

Stiffness to Weight: Bending, points		24
Stiffness to Weight: Bending, points		25

Strength to Weight: Axial, points		34 to 45
Strength to Weight: Axial, points		21

Strength to Weight: Bending, points		27 to 32
Strength to Weight: Bending, points		20

Thermal Shock Resistance, points		25 to 33
Thermal Shock Resistance, points		14

Alloy Composition

Aluminum (Al), %		0
Aluminum (Al), %		0 to 0.25

Carbon (C), %		0.15 to 0.35
Carbon (C), %		0 to 0.1

Chromium (Cr), %		26 to 30
Chromium (Cr), %		48 to 52

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

Iron (Fe), %		0 to 0.75
Iron (Fe), %		0 to 1.0

Manganese (Mn), %		0 to 1.0
Manganese (Mn), %		0 to 0.3

Molybdenum (Mo), %		5.0 to 7.0
Molybdenum (Mo), %		0

Nickel (Ni), %		0 to 1.0
Nickel (Ni), %		44.5 to 52

Nitrogen (N), %		0 to 0.25
Nitrogen (N), %		0 to 0.3

Phosphorus (P), %		0
Phosphorus (P), %		0 to 0.020

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

Sulfur (S), %		0
Sulfur (S), %		0 to 0.020

Titanium (Ti), %		0
Titanium (Ti), %		0 to 0.5