Phosphorus-Copper master alloys applications
Phosphorus-Copper master alloys are generally used for deoxidizing copper and copper alloys but also serve as alloying and wetting agent.
Deoxidant
Even though there are many other deoxidants available, phosphorus has demonstrated to be the most economical. The addition of Phosphorus-Copper removes oxygen and impurities from copper baths. It produces a cleaner product, free of cupric oxide, and generates a very liquid characteristic slag.
The reaction to the addition is instant: the quickly dissolved product reacts with the oxygen making the bath boil and producing a gas completely eliminated from the alloy. The reaction is highly exothermic: just adding 1% to the oven is able to raise the temperature by 40-50 ºC (it is added with the burner of the oven turned off).
In order to avoid re-oxidation we recommend adding our Phosphorus-Copper alloy as late as possible in your process. Also as excess phosphorus substantially reduces electrical conductivity add only enough phosphorus to remove the oxygen.
Remark: Phosphorus-Copper master alloys serve as an efficient deoxidant for Copper-Lead-Tin, Copper-Tin-Zinc, and Copper-Tin casting alloys. Nevertheless, they cannot be used for deoxidizing high conductivity copper as phosphorus is detrimental to electrical conductivity, also it is not possible to use them for copper-nickel alloys.
Alloying agent
CuP master alloys also serve as an alloying agent. The addition of a certain amount of phosphorus in copper alloys, including phosphor bronze and many different brazing alloys, increases the fluidity of the metal.
It also increases the strength, hardness and elasticity, while reducing creep and grain growth.
Wetting agent in brazing alloys
Phosphorus-Copper is also used as a wetting agent in brazing alloys. Brazing rod producers add phosphorus to brazing rod compositions to lower melting temperatures and improve wetting characteristics.
This addition will clean the brazed joint and improve its strength.