Copper Alloys, BrassCW614N (CZ121) Bar

A free machining brass with the highest possible machinability rating.

Free machining grades of brass set the standard for machining, by which other metals are compared and CZ121 offers the highest possible machinability of any copper alloy.

Brasses are alloys of copper and zinc and CZ121 is an alpha/beta alloy that contains 37-45% zinc. It also has a 3% lead content to improve machinability. The lead remains insoluble in the microstructure of the brass and the soft particles act as chip breakers.

CZ121 is the most widely used of all the brasses due to its suitability for high speed machining operations and also the manufacture of intricate parts. Its combination of machinability, thread rolling and knurling characteristics, combined with its good strength, an ease of soldering/brazing and a high resistance to corrosion makes it the ideal choice for many brass components throughout industry.

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Product FormImperial SizesMetric Sizes
Round Bar18" 4 12"3.0mm - 255.0mm
Hexagon Bar0.248" 3"5.0mm - 65.0mm
Square Bar14" 3"
Flat Bar38" x 18" 4" x 2"
If you do not see what you are looking for, please contact your local service centre with your specific requirements.

Related Specifications

CZ121/CW614N corresponds to the following designations but may not be a direct equivalent:

  • UNS C38500
  • CuZn39Pb3


Chemical Composition


  • High speed machined components
  • Architectural extrusions
  • Locks
  • Hinges
  • Nuts, bolts, bushings & bearings
  • Window frames


  • Highest machinability of any copper alloy
  • Good corrosion resistance
  • Good strength
  • Excellent hot formability

Additional Information


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