Copper Phosphorus (CuP) Master Alloys
High-Efficiency Deoxidants & Alloying Agents
Our Copper-Phosphorus (CuP) master alloys are the industry standard for precision deoxidation and alloying. Highly economical and efficient, these alloys are essential for producing high-quality phosphor bronze, brazing alloys, and controlling silicon morphology in aluminium foundry applications.
Economical Purifier
Proven as the most cost-effective agent for the deoxidation of copper and various copper-based alloys.
Fluidity Enhancer
Commonly added to brazing alloys and phosphor bronze to increase metal fluidity and control phosphorus levels.
Microstructure Control
CuP8% is utilised to refine the primary silicon phase in hypereutectic AlSi alloys, increasing toughness and wear resistance.
Technical Specifications (Weight %)
| Master Alloy | P (%) | Al max. | As max. | Bi max. | Fe max. | Mn max. | Ni max. | Pb max. | Sb max. | Se max. | Si max. | Sn max. | Te max. | Zn max. | Other Max. |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CuP8 (A) | 7.5 – 8.5 | 0.02 | 0.01 | 0.05 | 0.10 | 0.10 | 0.10 | 0.03 | 0.01 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.30 |
| CuP8 (B) | 7.5 – 8.5 | – | – | – | 0.20 | – | 0.20 | 0.20 | – | – | – | 0.20 | – | 0.20 | 0.50 |
| CuP10 (A) | 9.5 – 11.0 | 0.02 | 0.01 | 0.05 | 0.10 | 0.10 | 0.10 | 0.03 | 0.01 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.30 |
| CuP10 (B) | 9.5 – 11.0 | – | – | – | 0.20 | – | 0.20 | 0.20 | – | – | – | 0.20 | – | 0.20 | 0.50 |
| CuP15 (A) | 13.5 – 15.0 | 0.02 | 0.01 | 0.05 | 0.10 | 0.10 | 0.10 | 0.03 | 0.01 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.30 |
| CuP15 (B) | 13.5 – 15.0 | – | – | – | 0.10 | – | 0.10 | 0.10 | – | – | – | 0.10 | – | 0.10 | 0.40 |
| CuP15 (C) | 13.5 – 15.0 | – | – | – | 0.20 | – | 0.20 | 0.20 | – | – | – | 0.20 | – | 0.20 | 0.50 |
*Data sourced from KBM AFFILIPS CuP technical data sheet (2023-01). Specifications align with EN 1981:2003. Other grades and packaging available upon request.
Physical Properties & Melting Points
View Melting Point Data +
- CuP 8%: 714 °C
- CuP 10%: 850 °C
- CuP 15%: 1020 °C
Standard Formats: Supplied in 12–18 kg Waffle Plates (on wooden pallets) or as Shot (packed in steel drums).
Copper-Phosphorus FAQ
How should CuP be added to the melt? +
Remove all dross from the bath surface and add the required amount at normal operating temperatures. Stir well for homogeneous dissolution. Start casting immediately, as phosphorus tends to fade over time.
When is Copper-Phosphorus NOT suitable? +
CuP is unsuitable for high conductivity copper (as it reduces electrical conductivity) and copper-nickel alloys (where it causes grain boundary embrittlement).
How should Copper-Phosphorus be stored? +
Store in a dry area to prevent oxidation. Reaction with humidity will manifest as bluish crystals on the product surface.
What is the recommended residual phosphorus level when using Copper-Phosphorus Master Alloys for deoxidation? +
During the casting process, it is common practice to aim for a residual phosphorus level of 0.010 to 0.015% to effectively prevent reoxidation.