Copper-Phosphorus alloys have outstanding brazing properties and wide capabilities. Phosphorus will alloy readily with copper. Phosphorus is a reducing agent for copper and also deoxidizes silver. These brazing alloys of copper-phosphorus and silver-copper-phosphorus are self-fluxing on pure copper.

The reduction of phosphorus and additions of silver have a profound effect upon the fluidity of brazing alloys. The alloys of higher phosphorus content are extremely fluid, while the lower phosphorus, high silver alloy has a broad plastic range. Even small adjustments in alloy percentages have a marked effect on brazing alloy fluidity.