Free Cutting Brass C36000 is nominally composed of 61.5% copper, 35.4% zinc, and 3.1% lead. It is the alloy most often used for continuous high-speed machining operations. This is because its high lead content creates machined chips which are short and easily freed from the work, hence, the name “free-cutting.” This results in minimal tool wear and breakage with minimum downtime during machining. Alloy C36000 is thus considered the standard free-cutting copper alloy, and, as a result, its machinability index has been arbitrarily rated at 100, thereby becoming the standard to which all other copper alloys are compared. In volume, C36000 rod is probably used more than all other copper alloys combined.

Characteristics

Free Cutting Brass C36000 is nominally composed of 61.5% copper, 35.4% zinc, and 3.1% lead. It is the alloy most often used for continuous high-speed machining operations.

Hot Working and Cold Working

C36000 has fair hot workability. It can be hot worked if mechanically supported. It can be extruded readily and may be forged or hot rolled. Due to its high lead content, it has poor cold workability. Although it can withstand a limited amount of cold work, non-leaded brasses of higher copper content are much more suitable for cold working applications. Common fabrication processes are machining, roll threading and knurling.

Joining

Joining by soldering is excellent, while good by brazing. The lead content prevents successful welding.

Typical Uses

Hardware such as gears and pinions where excellent machinability is an important requirement, as well as for all types of automatic high-speed screw machine products.