Mechanical Properties of Brass
The mechanical properties of brass are different from each other due to the different zinc content. For alpha brass, as the amount of zinc increases, both σb and δ increase. For (α+β) brass, the room temperature strength is continuously increased before the zinc content is increased to about 45%. If the amount of zinc is further increased, the r phase having a greater brittleness (solid solution based on a Cu5Zn8 compound) appears in the alloy structure, and the strength is drastically lowered. The room temperature ductility of (α+β) brass always decreases with increasing zinc content. Therefore, copper-zinc alloys containing more than 45% zinc have no practical value.
Ordinary brass is widely used such as water tank belts, water supply and drainage pipes, medals, bellows, serpentine tubes, condensing tubes, shells and various shapes of complex products, small hardware and so on. With the increase of zinc content from H63 to H59, they can withstand the hot processing well, and are used in various parts of machinery and electrical appliances, stamping parts and musical instruments.
In order to improve the corrosion resistance, strength, hardness and machinability of brass, the copper-zinc alloy will be added a small amount of tin, aluminum, manganese, iron, silicon, nickel, lead and other elements to form ternary alloy, quaternary alloy, or even quinary alloy. The elemental alloy is a complex brass, also known as special brass.