Leaded naval brass C48500 is nominally composed of 60% copper, 37.5% zinc, 1.8% lead, and 0.7% tin. As is typical of brass alloys with the duplex alpha + beta structure, C48500 has good strength and rigidity. By substituting tin for an equal quantity of zinc, a high corrosion resistance to seawater is achieved. The addition of tin also gives the alloy an inherent resistance to dezincification, thereby further inhibiting the impingement by seawater at higher than normal temperatures. The addition of lead improves machinability, so C48500 is used in machining applications where unleaded Naval Brass C46400 might be the choice. The alloy is also noted for its resistance to wear, fatigue, galling, and stress corrosion cracking.

Characteristics

Hot Working

C48500 has good hot workability. Characteristically it becomes extremely plastic when hot and is fairly well adapted to any hot working process including hot forging and pressing and hot heading and upsetting.

Cold Working

Due to its lead content, C48500 has poor cold workability. Because it can be cold worked only to a very limited degree, it is used for machining applications rather than typical cold working operations such as blanking, drawing, forming, bending, shearing, heading and upsetting.

Joining

Joining by soldering is excellent, while good by brazing. The lead content prevents successful welding.

Typical Uses

C48500 is typically used for fasteners, valve stems, screw machine products, and marine hardware.