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Johnson Matthey CopperFlo No.3

Copper-flo™No.3 is a copper-phosphorus brazing filler metal containing a nominal 6.2% phosphorus and conforming to EN 1044 1999 CP203. It is primarily used for the brazing of copper tubes and pipes in refrigerationand air-conditioning applications and is a popular choice for this type of work. 

When it is used to braze copper the phosphorus within the alloy imparts a metallurgical based self-fluxing capability. If used to join copper alloys (such as brass, bronze or gun metal) a separate flux will be required because the self-fluxing action only occurs on copper (see below for details). 

This filler metal should not be used to braze iron containing materials like carbon or stainless steels or nickel containing materials as the phosphorus within the filler metal will form brittle, inter-metallic, phosphide compounds at the joint interface. Copper-flo™No.3 is not suitable for use in joints exposed to sulphurous atmospheres atelevated service temperatures.

Key Products Features & Benefits: 

  • 93.8% Copper (Cu) - 6.2% Phosphorous (P)
  • Melt Range - 714-890 ºC
  • Classified as CP 203 to EN1044 1999 Specification.
  • Classified as CuP 179 to ISO17672 2010 Specification
  • Commonly available as a 2.0mm Dia. rod as 
  • Standard 500mm long


Data Sheets and Info

Technical Bulletin

Product Guide

Related Technical Documents

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