ASTM B780 Alloy vs. EN 1.7709 Steel

ASTM B780 alloy belongs to the otherwise unclassified metals classification, while EN 1.7709 steel belongs to the iron alloys. There are 15 material properties with values for both materials. Properties with values for just one material (13, in this case) are not shown.

For each property being compared, the top bar is ASTM B780 alloy and the bottom bar is EN 1.7709 steel.

ASTM B780 Silver-Copper-Nickel Electrical Contact Alloy EN 1.7709 (21CrMoV5-7) Steel

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		83
Elastic (Young's, Tensile) Modulus, GPa		190

Poisson's Ratio		0.36
Poisson's Ratio		0.29

Shear Modulus, GPa		30
Shear Modulus, GPa		73

Tensile Strength: Ultimate (UTS), MPa		330 to 590
Tensile Strength: Ultimate (UTS), MPa		650 to 780

Thermal Properties

Latent Heat of Fusion, J/g		140
Latent Heat of Fusion, J/g		250

Specific Heat Capacity, J/kg-K		270
Specific Heat Capacity, J/kg-K		470

Thermal Expansion, µm/m-K		18
Thermal Expansion, µm/m-K		11

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS		70 to 76
Electrical Conductivity: Equal Volume, % IACS		7.5

Electrical Conductivity: Equal Weight (Specific), % IACS		62 to 68
Electrical Conductivity: Equal Weight (Specific), % IACS		8.6

Otherwise Unclassified Properties

Density, g/cm³		10
Density, g/cm³		7.8

Common Calculations

Stiffness to Weight: Axial, points		4.5
Stiffness to Weight: Axial, points		13

Stiffness to Weight: Bending, points		14
Stiffness to Weight: Bending, points		24

Strength to Weight: Axial, points		9.1 to 16
Strength to Weight: Axial, points		23 to 27

Strength to Weight: Bending, points		11 to 15
Strength to Weight: Bending, points		21 to 24

Thermal Shock Resistance, points		16 to 29
Thermal Shock Resistance, points		22 to 26

Alloy Composition

Aluminum (Al), %		0
Aluminum (Al), %		0 to 0.030

Cadmium (Cd), %		0 to 0.050
Cadmium (Cd), %		0

Carbon (C), %		0
Carbon (C), %		0.17 to 0.25

Chromium (Cr), %		0
Chromium (Cr), %		1.2 to 1.5

Copper (Cu), %		23.5 to 25.7
Copper (Cu), %		0

Iron (Fe), %		0 to 0.050
Iron (Fe), %		95.2 to 97.5

Lead (Pb), %		0 to 0.030
Lead (Pb), %		0

Manganese (Mn), %		0
Manganese (Mn), %		0.4 to 0.8

Molybdenum (Mo), %		0
Molybdenum (Mo), %		0.55 to 0.8

Nickel (Ni), %		0.35 to 0.65
Nickel (Ni), %		0 to 0.6

Phosphorus (P), %		0
Phosphorus (P), %		0 to 0.025

Silicon (Si), %		0
Silicon (Si), %		0 to 0.4

Silver (Ag), %		74 to 76
Silver (Ag), %		0

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

Vanadium (V), %		0
Vanadium (V), %		0.2 to 0.35

Zinc (Zn), %		0 to 0.060
Zinc (Zn), %		0