What Is Copper Nickel 90/10 (C70600 / CuNi10Fe1Mn)? 

Copper Nickel 90/10 — also known as CuNi 90/10, cupro nickel 90/10, UNS C70600, CuNi10Fe1Mn, DIN 2.0872, or CW352H — is a copper-based alloy containing approximately 10% nickel, with controlled additions of iron (1.0–1.8%) and manganese (0.5–1.0%). It is the most widely specified copper-nickel alloy for marine seawater service, offering exceptional resistance to seawater corrosion, erosion-corrosion, biofouling, and stress corrosion cracking. 

The iron and manganese additions in CuNi10Fe1Mn are not incidental — they are essential to the alloy’s corrosion performance. Iron forms a stable, adherent iron oxide film on the surface under flowing seawater conditions. This film acts as a diffusion barrier that dramatically reduces corrosion rates in both quiescent and turbulent seawater environments. Manganese stabilises this film and acts as a deoxidiser during casting and fabrication. Without these additions, a 90/10 copper-nickel alloy would perform significantly worse in marine service. 

CuNi 90/10 also has excellent weldability — it is readily joined using ERNiCu-7 or ERCuNi filler metals with GTAW (TIG) or GMAW (MIG) processes, making it straightforward to fabricate into complex marine piping systems and pressure components. Preheating is generally not required for sections under 25 mm. 

At Nifty Alloys, we supply Copper Nickel C70600 in round bars, plates, and tubes from our Dubai warehouse, backed by EN 10204 3.1 mill test certificates, available for immediate dispatch to UAE, GCC, and global marine, offshore, and desalination project destinations.