Selectarc PHOSBRAZ AG4

PHOSBRAZ AG4 is a copper-phosphorus-silver alloy (CuP-Ag) formulated for manual brazing applications. It’s designed to lower the liquidus point, refining the alloy and enhancing its properties. Specifically, it improves electrical conductivity, ductility, and resistance to vibration and cyclic pressure. This alloy provides good fluidity when brazing copper sleeves, tubes, and connections, resulting in strong, leak-proof joints. It’s valued for its gap-filling capabilities and is particularly suitable for bridging larger gaps. However, it’s crucial to note that this alloy shouldn’t be used with sulfur-containing media or with steel or iron-containing materials, as it can lead to brittle phase formation within the joint. Its corrosion resistance is comparable to copper under normal conditions, but may degrade in the presence of sulfur or at elevated temperatures.

PHOSBRAZ AG4 is primarily used in plumbing, electrical components, refrigeration, and heating/ventilation systems. It’s an economical choice for joining copper to copper, and can also be used with low-zinc brasses using Phosbraz flux. In air conditioning and refrigeration applications, it’s suitable for service temperatures ranging from +150 ˚C (without loss of strength) up to -20 ˚C. It can be applied with flame. The properties of the brazed joint are influenced by several factors including the base metal’s characteristics, joint design, and metallurgical interactions. It’s important to consider these factors when selecting appropriate preform sizes and heat source recommendations.