Inconel 718 (UNS N07718 / W.Nr. 2.4668)

Inconel 718 (UNS N07718 / W.Nr. 2.4668) is a precipitation-hardenable nickel-chromium alloy also containing significant amounts of iron, niobium, and molybdenum along with lesser amounts of aluminum and titanium. It combines corrosion resistance and high strength with outstanding weldability including resistance to post weld cracking. The alloy has excellent creep-rupture strength at temperatures to 700℃.

Equivalent Grades

TrademarkGBGOSTASTMUNSDINW.Nr.NFBSJISSS
Inconel 718GH4169Inconel 718N07718NiCr19Fe19Nb5Mo32.4668NiCr19Fe19Nb5Mo3NiCr19Fe19Nb5Mo3
ATG C1

Chemical Composition, %

AlloyCSiMnPSCrNiCoMoNb+TaAlTiCuFe
Inconel 718≤0.08≤0.35≤0.35≤0.015≤0.01517.0-21.050.0-55.0≤1.02.8-3.34.75-5.500.2-0.80.65-1.15≤0.30Bal

Typical Physical and Mechanical Properties (RT, Annealed+Aged)

Density, g/cm3Melting Point, ℃Tensile Strength, MPaYield Strength, MPaELongation, %Hardness, HRB
8.191260-1336≥1275≥1034≥331

Available Products and Specifications

Rod, Bar, Wire and ForgingsASTM B637/ASME SB637, ISO 9723/9724/9725, DIN 17752-17754
Plate, Sheet and StripASTM B670/ASME SB670, ASTM B906/ASME B906, ISO 6208, DIN 17750
Pipe and TubeSAE AMS 5589/5590, DIN17751
Welding ProductInconel Filler Metal 718-AWS A5.14/ERNiCrFe-2
OthersASTM B366/ASME SB366(Fittings), DIN 17744

Features

  • Good mechanical properties – tensile, fatigue and creep-rupture
  • Yield tensile strength, creep, and rupture strength properties are exceedingly high
  • Highly resistant to chloride and sulfide stress corrosion cracking
  • Resistant to aqueous corrosion and chloride ion stress corrosion cracking
  • High temperature resistant
  • Age-hardenable with a unique property of slow aging response that permits heating and cooling during annealing without the danger of cracking.
  • Excellent welding characteristics, resistant to postweld age cracking

Applications

  • Chemical processing
  • Aerospace
  • Liquid fuel rocket motor components
  • Pollution-control equipment
  • Nuclear reactors
  • Cryogenic storage tanks
  • Valves, fasteners, springs, mandrels, tubing hangers
  • Well head completion equipment and blow out preventers (BOP’s)
  • Gas turbine engine parts