CZ128 Brass

CZ128 (CW612N) has a much higher copper content resulting in an alloy with improved malleability and hot-forming capabilities.

Known as a free-machining or hot-stamping brass alloy, CZ128 provides superior machinability and finds use in producing turned parts and fittings. With excellent hot-forming characteristics, the alloy is ideal for hot stamping since the alloy does not deform during such processes. The material offers some cold workability, although bending is limited.


Typical commercial applications include:

  • Improved ductility
  • Good hot forming capabilities
  • Some cold workability
  • Free machining alloy
Use in valve manufacture

CZ128 is the specific alloy for producing pressurised carbon dioxide cylinder valves. Other brasses often fail in this scenario due to stress corrosion cracking inside the valve, and CZ128 is now the alloy of choice for this purpose. The alloy is classed as alpha brass because it contains less than 37% zinc making the material more malleable.


CZ128 (CW612N) finds particular use in producing high-pressure valves, especially carbon monoxide cylinder valves. Other applications include the production of complex parts and window fittings.

Material Specifications

CuZn38Pb2, CW608N, C37700, CZ128, CuZn38Pb2

Availability & Processing

We stock CZ128 brass alloy in round bars, sheets and plates, which we process in-house to your size requirements. We utilise bar saws, CNC plate saws and guillotines to cut your engineering materials to your chosen size requirements.

CZ128 brass
CZ128 pdf
CZ128 Stock

Product Summary

Product CZ128
Type Free Machining Brass
Availability Round bar, sheet and plate
Benefits Free machining alloy, good hot forming capabilities, some cold workability, improved ductility
Applications High pressure valves, carbon monoxide cylinder valves, complex parts, window fittings
Datasheet CZ128 - Technical Datasheet
Reference Home/ Products/ Brass Alloys/ CZ128

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