Bronze / Gunmetal

Bronze / Gunmetal are Copper alloy based materials with addition of;

  • Tin (Sn)
  • Lead (Pb)
  • Zinc (Zn)
  • Nickel

These materials are also known as Leaded Gunmetal, Steam or Valve Bronze, Composition Bronze or Ounce Metal

Common Material Specifications

Cu Sn5 Pb5 Zn5

  • ASTM B62 =UNS C83600
  • BS1400: LG2
  • EN1982: CC491K

Cu Sn7 Pb3 Zn2

  • BS1400 LG4
  • EN1982 CC492K

Cu Sn7 Pb1.5 Zn4

  • ASTMB61 = UNS C92200

Typical Properties

  • Tensile 200-250 N/mm2
  • Yield 90-100 N/mm2
  • Elongation 13- 24%
  • Hardness HB60
  • Density 8.8 g/cm3
  • Good castability, non-magnetic, excellent bearing material, easy machining, good impact values
  • PT Rating B16.24-2006 / EN1759-3:2003
  • 15.5 bar for Class 150

Corrosion Properties

  • Good for seawater service
  • Especially good for slow flow, general corrosion and crevice corrosion
  • Excellent fouling resistance

Additional Uses & Comments

  • Non-sparking, excellent impact properties, good for Oxygen and cryogenic applications
  • Non-magnetic
  • Good thermal and electrical conductivity
  • Castabilty allows consistent thin sections
  • Excellent bearing material

Cautions

  • Poor weldability
  • Low modulus of elasticity, low yield stress
    • Avoid raised face flanges!
    • Beware pressure ratings
  • Limited high temperature use