Hidurel 5 (UNS S64700 CuNi2Si)


Hidurel® 5 is a precipitation-hardening copper-nickel-silicon alloy possessing high electrical and thermal conductivity with very good notch ductility and high mechanical strength. Annealing at elevated temperature creates a soft supersaturated alpha-phase structure, before subsequent age hardening at lower temperature precipitates finely dispersed nickel silicide in the matrix. Despite its high strength, the alloy is resistant to hydrogen embrittlement. Resistance to corrosion under marine and industrial conditions is excellent and the alloy has good anti-frictional and bearing properties. With a magnetic permeability of less than 1.001, the alloy is essentially non-magnetic.

The excellent combination of properties provided by Hidurel® 5 is the result of careful control of chemical composition and heat treatment. Tensile properties are uniform and virtually independent of section thickness. The heat treatment of the alloy also ensures dimensional stability of a high order.

Hidurel® 5 meets the mechanical and chemical properties of DTD 498, BS 4577 Type A3/2 and Rolls Royce MSRR 8501 to which Langley Alloys regularly supply so can therefore be specified in confidence for high integrity components. Cold worked material to DTD 504 can also be supplied to order.


Key Features:

  • High strength with good electrical and thermal conductivity
  • Resistant to hydrogen embrittlement
  • Excellent bearing and anti-friction properties, particularly when operated against hardened steel
  • Excellent corrosion resistance in marine environments
  • Very low magnetic permeability - less than 1.001
  • No loss of impact strength down to -196°C
  • Spark resistance
  • Good elevated temperature properties
  • Ease of machining
  • Good marine fouling resistance


  • Naval applications including shafts, bolting for ships & submarines, flanges, swash plate pump components, mine detection equipment
  • Automotive components such as valve guides & seats, small end bushes, camshaft bushes, brake caliper pads, fuel pump parts
  • Resistance welding electrodes
  • Plastic moulding dies, electrical forging dies, die grips on upsetting machines
  • Aerospace components including engine bearing cages, undercarriage components, heavily loaded bearings, helicopter shafts, head-up display parts
  • Gears, piston crowns, clutch plates in marine engines, electrical contacts, hose connectors
  • Thrust pads, slipper pads, mechanical seals, bushes in subsea valves
  • Valve bodies

Chemical Composition:

Cr Ni Mo Co Nb (+Ta) Ti V W Cu C Mn N Si P S Fe Al
Min 2.30 0.05 0.40
Max 3.50 Bal 0.30 0.80 0.10 0.02

Mechanical Properties:

Supplied to BSB25 Supplied to DTD498 Supplied to DTD 504 (Cold Drawn)
0.1% Proof Stress 417 N/mm2 60.5ksi 417 N/mm2 60.5ksi 572 N/mm2 82.9ksi
0.2% Proof Stress 430 N/mm2 62.4ksi
Tensile Strength 587 N/mm2 85.1ksi 587 N/mm2 85.1ksi 649 N/mm2 94.1ksi
Elongation, 4D 18% 15% 10%
Hardness (Brinnel) 159-207HBN 159-207HBN 174-210 HBN
Impact Strength (Room Temp) 27J 27J


  1. Testing shall be carried out in accordance with ASTM A370 or EN ISO 6892-1 (tensile), EN ISO 6506-1 (hardness)
  2. Minimum properties quoted (tested at room temperature in a longitudinal direction)
  3. Testing performed on each melt of material per heat treatment batchUN

Physical Properties:

Density (Kg/m3) 8870
Magnetic Permeability (20°C) < 1.001
Young’s Modulus (kN/mm2) 284
Modulus of Rigidity (kN/mm2) 106
Poissons Ratio 0.39
Specific Electrical Resistance, 20°C (Ω-m) 0.043
Electrical Conductivity, 20°C (mΩ/mm2) 6.9 (40% IACS)
Mean coefficient of thermal expansion, 20-400°C (m/m/degC) 16 x 10-6
Specific Heat, 20°C (J/kg.K) 419
Thermal conductivity, 20°C (W/m.K) 190
Thermal conductivity, 200°C (W/m.K) 211
Thermal conductivity, 400°C (W/m.K) 232
Coefficient of static friction against mild steel 0.45-0.50
Coefficient of dynamic friction against mild steel 0.26 (dry), 0.33 (wet)


Datasheet - CA-Hidurel 5

Datasheet - CA-Hidurel 5

Brochure - Hidurel 5 - Detailed product information

Brochure - Hidurel 5 - Detailed product information