copperzinc

Copper-zinc alloys, commonly known as brass, are copper-based alloys in which zinc is the principal alloying element. The term copper-zinc can refer to the broader family of brass alloys, which are distinct from bronze (copper-tin) and other copper alloys. Brass encompasses a range of compositions and properties shaped by zinc content and processing.

Zinc content in brass typically ranges from about 5 to 45 percent by weight. Lower zinc contents produce soft, ductile alpha brass, while higher contents yield stronger, more rigid beta brass; some grades achieve a balance of strength and machinability. Certain brass alloys also include small amounts of lead or other elements to improve machinability and tool wear resistance.

Brass generally offers good formability and machinability, along with decent corrosion resistance in many environments. Its electrical conductivity is lower than that of pure copper and decreases as zinc content increases. Brass often displays a characteristic yellowish to reddish-gold color, which makes it popular for decorative hardware and musical instruments, as well as plumbing fittings and valves. Leaded variants are widely used for precision machining.

Common applications include decorative hardware, musical instruments (brass instruments), valves, fittings, and heat exchangers. In service, brass can be susceptible to dezincification—a selective leaching of zinc in certain aggressive aqueous environments—which can weaken the material. Heat treatment and cold working can also modify its mechanical properties and performance.

Overall, copper-zinc alloys are valued for their combination of workability, corrosion behavior, and distinctive appearance, with a wide range of grades tailored to specific applications.