Brass is an alloy that is comprised of Copper and Zinc. Different grades of Brass will also contain elements of other alloys that will provide different properties. Brass has a high tensile strength, high corrosion resistance and is suitable to be hot forged.
Brass is separated into two types of class. Alpha alloys contain less than 37% Zinc in them, are ductile and can be cold worked. Alpha/beta alloys contain 37-45% Zinc and are both harder and stronger but are less cold ductility.
CZ121 Brass is an alpha/beta alloy that is very well suited for machining. This improved machining is due to lead that had been added to the Brasses composition. The added lead is insoluble in the Brasses microstructure so the soft particles act as chip breakers.
Because of this CZ121 is also referred to as CZ121M to show its machining properties.
CZ212 has good-excellent corrosion resistance.
Cold working of CZ121 is not good and not recommended, although it can be knurled if needed.
Chemical Composition of CZ121
CZ121 is well suited for soldering and rated good for brazing, however butt welding is only rated as fair and all other methods of welding are not recommended.
Mechanical Properties of CZ121
|Grade||Tensile Strength (MPa)||Proof Stress 0.2% (MPa)||Hardness VPN||Elongation %|
Physical Properties of CZ121
|Density||Melting Point||Modulus of Elasticity||Thermal Conductivity||Thermal Expansion||Electrical Resistivity|
|8.47 g/cm3||875°C||97 GPa||123 W/m.K at 100°C||20.9 x10-6 /K at 100°C||0.062x10-6 Ω.m|