C68800 Brass vs. ASTM B780 Alloy

C68800 brass belongs to the copper alloys classification, while ASTM B780 alloy belongs to the otherwise unclassified metals. They have a modest 25% of their average alloy composition in common, which, by itself, doesn't mean much. There are 17 material properties with values for both materials. Properties with values for just one material (14, in this case) are not shown.

For each property being compared, the top bar is C68800 brass and the bottom bar is ASTM B780 alloy.

UNS C68800 Aluminum Brass ASTM B780 Silver-Copper-Nickel Electrical Contact Alloy

Metric UnitsUS Customary Units

Mechanical Properties

Elastic (Young's, Tensile) Modulus, GPa		110
Elastic (Young's, Tensile) Modulus, GPa		83

Elongation at Break, %		2.0 to 36
Elongation at Break, %		1.1 to 9.1

Poisson's Ratio		0.32
Poisson's Ratio		0.36

Shear Modulus, GPa		41
Shear Modulus, GPa		30

Shear Strength, MPa		380 to 510
Shear Strength, MPa		200 to 340

Tensile Strength: Ultimate (UTS), MPa		570 to 890
Tensile Strength: Ultimate (UTS), MPa		330 to 590

Thermal Properties

Latent Heat of Fusion, J/g		190
Latent Heat of Fusion, J/g		140

Specific Heat Capacity, J/kg-K		400
Specific Heat Capacity, J/kg-K		270

Thermal Expansion, µm/m-K		19
Thermal Expansion, µm/m-K		18

Electrical Properties

Electrical Conductivity: Equal Volume, % IACS		18
Electrical Conductivity: Equal Volume, % IACS		70 to 76

Electrical Conductivity: Equal Weight (Specific), % IACS		20
Electrical Conductivity: Equal Weight (Specific), % IACS		62 to 68

Otherwise Unclassified Properties

Density, g/cm³		8.2
Density, g/cm³		10

Common Calculations

Stiffness to Weight: Axial, points		7.3
Stiffness to Weight: Axial, points		4.5

Stiffness to Weight: Bending, points		19
Stiffness to Weight: Bending, points		14

Strength to Weight: Axial, points		19 to 30
Strength to Weight: Axial, points		9.1 to 16

Strength to Weight: Bending, points		19 to 25
Strength to Weight: Bending, points		11 to 15

Thermal Shock Resistance, points		19 to 30
Thermal Shock Resistance, points		16 to 29

Alloy Composition

Aluminum (Al), %		3.0 to 3.8
Aluminum (Al), %		0

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

Cobalt (Co), %		0.25 to 0.55
Cobalt (Co), %		0

Copper (Cu), %		70.8 to 75.5
Copper (Cu), %		23.5 to 25.7

Iron (Fe), %		0 to 0.2
Iron (Fe), %		0 to 0.050

Lead (Pb), %		0 to 0.050
Lead (Pb), %		0 to 0.030

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

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

Zinc (Zn), %		21.3 to 24.1
Zinc (Zn), %		0 to 0.060

Residuals, %		0 to 0.5
Residuals, %		0