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 Brass alloys
Brasses are alloys that are a raw combination of Copper and Zinc. It has a yellow colour, somewhat similar to gold. It is relatively resistant to tarnishing, and is often used as decoration. These have high corrosion resistance and high tensile strength and also suited to be fabricated by hot forging. Certain brasses can corrode in various environments. Aluminium makes brass stronger and more corrosion resistant.
Free machining grades of brass set the standard for machining by which other metals are compared. Brasses are divided into two classes. The alpha alloys, with less than 37% Zinc and the alpha/beta alloys with 37-45% zinc. Alpha alloys are flexible and can be cold worked. Alpha/beta or duplex alloys have limited cold ductility and are harder and stronger. By varying the proportions of copper and zinc, the properties of the brass can be changed, allowing hard and soft brasses. The relatively low melting point (900-940 degrees C depending on composition) of brass and its flow characteristics make it a relatively easy material to cast.
Brasses are used in applications such as blanking, coining, drawing, piercing, springs, fire extinguishers, jewelry, radiator cores, lamp fixtures, ammunition, flexible hose, and the base for gold plate. The cast brasses are used in applications such as plumbing fixtures, fittings and low-pressure valves, gears, bearings, decorative hardware and architectural trim. Brass alloys are very useful for architectural applications, high strength components, valves, valve stems, fittings, and marine fittings.
The malleability and acoustic properties of brass have made it the metal of choice for brass musical instruments such as the trumpet, tuba, trombone, saxophone, harmonica and euphonium. Brass has higher malleability than copper or zinc.
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