When brazing copper tube to wrought copper fittings, which filler metal can be used successfully without flux?

When brazing copper tube to wrought copper fittings, using BCuP as a filler metal is effective without the need for flux because it is specifically formulated for joining copper to copper. BCuP, also known as copper-phosphorus filler metal, contains phosphorus, which acts as a cleansing agent that helps remove oxides from the metal surfaces being joined. This characteristic is particularly beneficial because it enhances the wetting and flow of the filler metal, resulting in a strong, reliable joint.

The advantage of using BCuP without flux is significant in terms of simplifying the process and reducing the chance of contamination that can occur with flux usage. This can lead to cleaner joints and minimize the need for post-brazing clean-up. While other filler metals may require flux to facilitate the brazing process, BCuP's composition allows it to bond effectively without additional chemicals, making it a preferred choice for many pipe fitting applications involving copper materials.