Copper-nickel alloys

The addition of nickel to copper improves strength and corrosion resistance but good ductility is retained. Copper-nickel alloys have excellent resistance to marine corrosion.

The two main alloys are 90/10 and 70/30. The 70/30 is stronger and has greater resistance to seawater flow; but the 90/10 will provide good service for most applications and, being less expensive, tends to be more widely used.  Both alloys contain small but important additions of iron and manganese, which have been chosen to provide the best combination of resistance to flowing seawater and to overall corrosion.

Copper-nickel alloys are widely used for marine applications due to their excellent resistance to sea water corrosion and good fabricability. These copper alloys have provided reliable service for several decades whilst offering effective solutions to today’s technological challenges.


  • Seawater pipework
  • Offshore fire water systems
  • Heat exchangers and condensers
  • Sheathing of legs and risers on offshore platforms and boat hulls
  • Hydraulic lines
  • Fish cages for aquaculture
  • Desalination units