Brass


Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin.Bronze does not necessarily contain tin, and a variety of alloys of copper, including alloys with arsenic, phosphorus, aluminium, manganese, and silicon, are commonly termed “bronze”. The term is applied to a variety of brasses and the distinction is largely historical, both terms having a common antecedent in the term latten. Brass is a substitutional alloy. It is used for decoration for its bright gold-like appearance; for applications where low friction is required such as locks, gears, bearings, doorknobs, ammunition casings and valves; for plumbing and electrical applications; and extensively in musical instruments such as horns and bells for its acoustic properties. It is also used in zippers. Brass is often used in situations where it is important that sparks not be struck, as in fittings and tools around explosive gases.


Chemical Composition of Brasses
Material Normal Composition Nearest Relevant Composition Specification
BS : 2870 ISO JIS
95/5
Cap Copper
95% Cu, 5% Zn CZ 125 Cu Zn 5 H 3100
C 2100
90/10
Guilding Metal
90% Cu, 10% Zn  CZ101 Cu Zn 10
426/1
H 3100
C 2200
85/15
Guilding Metal
85% Cu, 15% Zn. CZ102 Cu Zn 15
426/1
H 3100
C 2300
80/20
Brass
80% Cu, 20% Zn. CZ103 Cu Zn 20
426/1
H 3100
C 2400
70/30
(Cartridge Brass)
70% Cu, 30% Zn. CZ106 Cu Zn 30
426/1
H 3100
C 2600
60/35
(2 and 1 Brass)
65% Cu, 35% Zn. CZ107 Cu Zn 35
426/1
H 3100
C 2680
63/37
(Common Brass)
63% Cu, 37% Zn CZ108 Cu Zn 37
426/1
H 3100
C 3560