NEW-Copper Nickel

Overview

Copper Nickel Alloys (90/10 & 70/30)

UK Stockist | DEF STAN 02-879 Compliant | Ultrasonically Tested | 3.2 Certified

Holme Dodsworth Metals are leading suppliers and stockholders of Copper Nickel 90/10 (CN102) and Copper Nickel 70/30 (CN107), two premium alloys renowned for their exceptional corrosion resistance, marine-grade durability, and high performance in seawater and chemical environments.

We hold an extensive range of ultrasonically tested CuNi bar stock with full 3.2 mill certification and compliance with DEF STAN 02-879 for use in defence and aerospace applications.

What is Copper Nickel?

Copper Nickel (CuNi) is a copper-based alloy containing nickel, iron, and manganese. It is widely used in industries where seawater corrosion, biofouling, thermal conductivity, and long-term structural integrity are key considerations.

Grades & Designations

Grade EN Designation CW Number UNS BS
CN102 (90/10) CuNi10Fe1Mn CW352H C70600 CN 102
CN107 (70/30) CuNi30Mn1Fe CW354H C71500 CN 107

Applications of Copper Nickel Alloys

Our CuNi 90/10 and 70/30 materials are used in a wide range of sectors, including:

  • Marine & Offshore Engineering – seawater piping, condensers, pump housings

  • Defence & Naval Systems – MOD-grade piping systems, marine structures (DEF STAN 02-879 compliant)

  • Aerospace Engineering – hydraulic tubing, anti-corrosive components

  • Desalination & Water Treatment – evaporators, brine heaters, condensers

  • Heat Exchange & HVAC – oil coolers, air conditioners, finned tubes

  • Automotive Systems – brake lines, fuel and hydraulic systems

  • Hygiene & Healthcare – antimicrobial surfaces for safety-critical environments

Copper Nickel Material Characteristics

CN102 – Copper Nickel 90/10 (CuNi10Fe1Mn)

  • Excellent corrosion resistance in saltwater, brine, and non-oxidising acids

  • Resists pitting, crevice corrosion, and stress corrosion cracking

  • Maintains structural integrity at flow rates up to 6 m/s in clean seawater

  • Excellent cold formability and weldability

  • Ideal for marine piping, oil & gas, HVAC, and military applications

  • Compliant with DEF STAN 02-879, EN 12163, and UNS C70600

Chemical Composition:

  • Cu: Balance

  • Ni: 9.0–11.0%

  • Fe: 1.0–2.0%

  • Mn: 0.5–1.0%

  • Pb, S, Sn: max 0.05%

  • Zn: max 0.5%

CN107 – Copper Nickel 70/30 (CuNi30Mn1Fe)

  • Higher nickel content for enhanced strength and corrosion resistance

  • Excellent performance in high-velocity seawater and polluted marine environments

  • Superior erosion and cavitation resistance

  • Used in high-pressure heat exchangers, power stations, and naval systems

  • Excellent for aerospace, subsea, and critical defence infrastructure

  • Compliant with EN 12163, DEF STAN 02-879, and UNS C71500

Typical Composition:

  • Cu: Balance

  • Ni: ~30%

  • Mn: ~1%

  • Fe: ~0.5–1%

  • Zn, Pb, S, C, Sn: low trace elements

Overview 
Shape Size Grade
Round Bar 1" 90/10 CN102
Round Bar 35mm 90/10 CN102
Round Bar 1 3/4" 90/10 CN102
Round Bar 2" 90/10 CN102
Round Bar 3" 90/10 CN102
Round Bar 6" 90/10 CN102
Round Bar 1" 70/30 CN107
Round Bar 35mm 70/30 CN107
Round Bar 1 3/4" 70/30 CN107
Round Bar 2" 70/30 CN107
Round Bar 2 1/2" 70/30 CN107
Round Bar 3" 70/30 CN107
Round Bar 4" 70/30 CN107
Round Bar 6" 70/30 CN107
Physical properties
Spec. heat 20° J/kg K 377
Thermal conductivity W/(mK) 46
Coefficient of thermal
expansion		 (20–100 °C) 10-6/K 17
Density g/cm3 8,9
Modul of elasticity GPa 130
Electrical resistance
(20°C annealed)		 μOhm
cm		 19
Overview
Fabrication properties
Forming   Surface treatment
Machinability Less suitable
(~20 %)		   Polishing  
Cold forming Excellent   Mechanical Good
Warm forming Good   Electrolyte Good
 
Joining   Heat treatment
WIG welding Excellent   Melting point 1130 - 1160°C
MIG welding Excellent   Hot working 950 – 1050°C
Hard soldering Excellent   Soft annealing 680 – 750°C
Soft soldering Excellent   Thermal stress relieving 400 – 450°C
Resistance welding Excellent      
 
Corrosion resistance   Product standards

Copper Nickel 90/10 exhibits excellent resistance to corrosion in seawater and brine environments, making it ideal for marine and offshore applications.

Excellent performance in hot seawater, with resistance to:

  • Pitting corrosion

  • Crevice corrosion

  • Stress corrosion cracking (SCC)

Copper Nickel 70/30 offers superior corrosion and erosion resistance compared to 90/10, due to its higher nickel content (~30%).

Excellent resistance to:

  • Biofouling and microbial-induced corrosion (MIC)

  • Stress corrosion and intergranular attack

  • Pitting and crevice corrosion

   Tube EN 12451
EN 12449
  Bars EN 12163
Mechanical properties (values can be achieved and are a function of size and form)
Reference values at 20°C Annealed R290 R310 R480
Tensile strength [MPa] ≥ 290 ≥ 310 ≥ 480
Yield strength [MPa] ≥ 90 ≥ 220 ≥ 400
Elongation A5 [%] ≥ 30 ≥ 12 ≥ 8
Vickers hardness 75 - 105 105 - 150 ≥ 150