C46400 Naval Brass

Naval Brass, internationally known by its UNS C46400 designation, is a high-strength copper-zinc alloy specifically engineered for superior corrosion resistance in marine environments. This alpha-beta brass enhances the standard 60/40 brass (CuZn40) composition with the addition of approximately 1% tin, drastically improving its ability to resist dezincification-a common failure mode in seawater applications. As a result, it is the material of choice for marine hardware, propeller shafts, forgings, and other critical structural components exposed to seawater. Its global acceptance is reflected in its various national standard designations, including CW712R (EN) for Europe, CuZn77Al2 / 2.0510 (DIN) for Germany, C4621 (JIS) for Japan, and ZCuZn77Al2 (GB) for China. While its mechanical properties are comparable to C28000 (Muntz Metal), the tin addition provides marginally higher strength and vastly superior corrosion performance, making it an indispensable alloy for marine engineering.

UNS C46400 is a leaded, alpha-beta duplex brass alloyed with ~1% Sn for enhanced corrosion resistance, particularly against dezincification in marine environments. Its mechanical properties are highly dependent on temper.

Typical Room-Temperature Properties (per ASTM B21, B124, B171):

Melting Point - Liquidus - 1650 F
Melting Point - Solidus - 1630 F
Density - 0.304 lb/in3 at 68 F
Specific Gravity - 8.41
Electrical Resistivity - 39.9 ohms-cmil/ft @ 68 F
Electrical Conductivity - 26 %IACS @ 68 F
Thermal Conductivity - 67.0 Btu · ft/(hr · ft2·oF)at 68F
Coefficient of Thermal Expansion - 11.8 ·10-6 per oF (68-572 F)
Specific Heat Capacity - 0.09 Btu/lb/oF at 68 F
Modulus of Elasticity in Tension - 15000 ksi
Modulus of Rigidity - 5600 ksi
Machinability Rating - 30%