AWS E240 vs. R31538 Cobalt

AWS E240 belongs to the iron alloys classification, while R31538 cobalt belongs to the cobalt alloys. They have a modest 20% of their average alloy composition in common, which, by itself, doesn't mean much. There are 21 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 AWS E240 and the bottom bar is R31538 cobalt.

AWS E240 (W32410) Weld Metal 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		200
Elastic (Young's, Tensile) Modulus, GPa		220

Elongation at Break, %		17
Elongation at Break, %		13 to 23

Poisson's Ratio		0.28
Poisson's Ratio		0.29

Shear Modulus, GPa		77
Shear Modulus, GPa		86

Tensile Strength: Ultimate (UTS), MPa		770
Tensile Strength: Ultimate (UTS), MPa		1020 to 1360

Thermal Properties

Latent Heat of Fusion, J/g		290
Latent Heat of Fusion, J/g		320

Melting Completion (Liquidus), °C		1390
Melting Completion (Liquidus), °C		1360

Melting Onset (Solidus), °C		1350
Melting Onset (Solidus), °C		1290

Specific Heat Capacity, J/kg-K		480
Specific Heat Capacity, J/kg-K		450

Thermal Conductivity, W/m-K		15
Thermal Conductivity, W/m-K		13

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

Otherwise Unclassified Properties

Density, g/cm³		7.7
Density, g/cm³		8.4

Embodied Carbon, kg CO₂/kg material		3.0
Embodied Carbon, kg CO₂/kg material		8.1

Embodied Energy, MJ/kg		42
Embodied Energy, MJ/kg		110

Embodied Water, L/kg		160
Embodied Water, L/kg		530

Common Calculations

Stiffness to Weight: Axial, points		14
Stiffness to Weight: Axial, points		15

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

Strength to Weight: Axial, points		28
Strength to Weight: Axial, points		34 to 45

Strength to Weight: Bending, points		24
Strength to Weight: Bending, points		27 to 32

Thermal Diffusivity, mm²/s		3.9
Thermal Diffusivity, mm²/s		3.5

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

Alloy Composition

Carbon (C), %		0 to 0.060
Carbon (C), %		0.15 to 0.35

Chromium (Cr), %		17 to 19
Chromium (Cr), %		26 to 30

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

Copper (Cu), %		0 to 0.75
Copper (Cu), %		0

Iron (Fe), %		58.6 to 68.4
Iron (Fe), %		0 to 0.75

Manganese (Mn), %		10.5 to 13.5
Manganese (Mn), %		0 to 1.0

Molybdenum (Mo), %		0 to 0.75
Molybdenum (Mo), %		5.0 to 7.0

Nickel (Ni), %		4.0 to 6.0
Nickel (Ni), %		0 to 1.0

Nitrogen (N), %		0.1 to 0.3
Nitrogen (N), %		0 to 0.25

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

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

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