AWS BVAg-8b vs. R30155 Cobalt

AWS BVAg-8b belongs to the otherwise unclassified metals classification, while R30155 cobalt belongs to the iron alloys. There are 15 material properties with values for both materials. Properties with values for just one material (18, in this case) are not shown.

For each property being compared, the top bar is AWS BVAg-8b and the bottom bar is R30155 cobalt.

AWS BVAg-8b (P07728) Vacuum Service Filler Metal UNS R30155 (formerly Grade 661) Iron-Cobalt Alloy

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		84
Elastic (Young's, Tensile) Modulus, GPa		210

Poisson's Ratio		0.36
Poisson's Ratio		0.29

Shear Modulus, GPa		31
Shear Modulus, GPa		81

Tensile Strength: Ultimate (UTS), MPa		170
Tensile Strength: Ultimate (UTS), MPa		850

Thermal Properties

Latent Heat of Fusion, J/g		140
Latent Heat of Fusion, J/g		300

Melting Completion (Liquidus), °C		800
Melting Completion (Liquidus), °C		1470

Melting Onset (Solidus), °C		780
Melting Onset (Solidus), °C		1420

Specific Heat Capacity, J/kg-K		280
Specific Heat Capacity, J/kg-K		450

Thermal Expansion, µm/m-K		19
Thermal Expansion, µm/m-K		14

Otherwise Unclassified Properties

Density, g/cm³		10
Density, g/cm³		8.5

Common Calculations

Stiffness to Weight: Axial, points		4.7
Stiffness to Weight: Axial, points		14

Stiffness to Weight: Bending, points		15
Stiffness to Weight: Bending, points		23

Strength to Weight: Axial, points		4.7
Strength to Weight: Axial, points		28

Strength to Weight: Bending, points		6.8
Strength to Weight: Bending, points		24

Thermal Shock Resistance, points		7.6
Thermal Shock Resistance, points		21

Alloy Composition

Cadmium (Cd), %		0 to 0.0010
Cadmium (Cd), %		0

Carbon (C), %		0 to 0.0050
Carbon (C), %		0.080 to 0.16

Chromium (Cr), %		0
Chromium (Cr), %		20 to 22.5

Cobalt (Co), %		0
Cobalt (Co), %		18.5 to 21

Copper (Cu), %		26.8 to 29.2
Copper (Cu), %		0

Iron (Fe), %		0
Iron (Fe), %		24.3 to 36.2

Lead (Pb), %		0 to 0.0020
Lead (Pb), %		0

Manganese (Mn), %		0
Manganese (Mn), %		1.0 to 2.0

Molybdenum (Mo), %		0
Molybdenum (Mo), %		2.5 to 3.5

Nickel (Ni), %		0.3 to 0.7
Nickel (Ni), %		19 to 21

Niobium (Nb), %		0
Niobium (Nb), %		0.75 to 1.3

Nitrogen (N), %		0
Nitrogen (N), %		0 to 0.2

Phosphorus (P), %		0 to 0.0020
Phosphorus (P), %		0 to 0.040

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

Silver (Ag), %		70.5 to 72.5
Silver (Ag), %		0

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

Tantalum (Ta), %		0
Tantalum (Ta), %		0.75 to 1.3

Tungsten (W), %		0
Tungsten (W), %		2.0 to 3.0

Zinc (Zn), %		0 to 0.0010
Zinc (Zn), %		0