Grade 364 Molybdenum vs. R31538 Cobalt

Grade 364 molybdenum belongs to the otherwise unclassified metals classification, while R31538 cobalt belongs to the cobalt alloys. There are 20 material properties with values for both materials. Properties with values for just one material (9, in this case) are not shown.

For each property being compared, the top bar is grade 364 molybdenum and the bottom bar is R31538 cobalt.

Grade 364 Molybdenum High Carbon Co-28Cr-6Mo Alloy (ASTM F1537 Alloy 2, ISO 5832-12 Alloy 2, R31538)

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		310
Elastic (Young's, Tensile) Modulus, GPa		220

Elongation at Break, %		6.2 to 11
Elongation at Break, %		13 to 23

Poisson's Ratio		0.31
Poisson's Ratio		0.29

Shear Modulus, GPa		120
Shear Modulus, GPa		86

Tensile Strength: Ultimate (UTS), MPa		580 to 720
Tensile Strength: Ultimate (UTS), MPa		1020 to 1360

Tensile Strength: Yield (Proof), MPa		350 to 620
Tensile Strength: Yield (Proof), MPa		580 to 930

Thermal Properties

Latent Heat of Fusion, J/g		370
Latent Heat of Fusion, J/g		320

Specific Heat Capacity, J/kg-K		250
Specific Heat Capacity, J/kg-K		450

Thermal Expansion, µm/m-K		7.0
Thermal Expansion, µm/m-K		13

Otherwise Unclassified Properties

Density, g/cm³		10
Density, g/cm³		8.4

Embodied Carbon, kg CO₂/kg material		28
Embodied Carbon, kg CO₂/kg material		8.1

Embodied Energy, MJ/kg		330
Embodied Energy, MJ/kg		110

Embodied Water, L/kg		360
Embodied Water, L/kg		530

Common Calculations

Resilience: Ultimate (Unit Rupture Work), MJ/m³		43 to 57
Resilience: Ultimate (Unit Rupture Work), MJ/m³		140 to 200

Resilience: Unit (Modulus of Resilience), kJ/m³		200 to 630
Resilience: Unit (Modulus of Resilience), kJ/m³		750 to 1920

Stiffness to Weight: Axial, points		17
Stiffness to Weight: Axial, points		15

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

Strength to Weight: Axial, points		16 to 20
Strength to Weight: Axial, points		34 to 45

Strength to Weight: Bending, points		15 to 17
Strength to Weight: Bending, points		27 to 32

Thermal Shock Resistance, points		19 to 24
Thermal Shock Resistance, points		25 to 33

Alloy Composition

Carbon (C), %		0.010 to 0.040
Carbon (C), %		0.15 to 0.35

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

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

Iron (Fe), %		0 to 0.010
Iron (Fe), %		0 to 0.75

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

Molybdenum (Mo), %		99.2 to 99.5
Molybdenum (Mo), %		5.0 to 7.0

Nickel (Ni), %		0 to 0.0050
Nickel (Ni), %		0 to 1.0

Nitrogen (N), %		0 to 0.0020
Nitrogen (N), %		0 to 0.25

Oxygen (O), %		0 to 0.030
Oxygen (O), %		0

Silicon (Si), %		0 to 0.0050
Silicon (Si), %		0 to 1.0

Titanium (Ti), %		0.4 to 0.55
Titanium (Ti), %		0

Zirconium (Zr), %		0.060 to 0.12
Zirconium (Zr), %		0