Inconel 718

Inconel 718

Inconel 718 is a nickel-chromium-molybdenum alloy designed to resist a wide range of severely corrosive environments, pitting and crevice corrosion. This nickel steel alloy also displays exceptionally high yield, tensile, and creep-rupture properties at high temperatures. This nickel alloy is used from cryogenic temperatures up to long term service at 1200° F. Inconel-718

One of the distinguishing features of Inconel 718’s composition is the addition of niobium to permit age hardening which allows annealing and welding without spontaneous hardening during heating and cooling. The addition of niobium acts with the molybdenum to stiffen the alloy’s matrix and provide high strength without a strengthening heat treatment. Other popular nickel-chromium alloys are age hardened through the addition of aluminum and titanium. This nickel steel alloy is readily fabricated and may be welded in either the annealed or precipitation (age) hardened condition. This superalloy is used in a variety of industries such as aerospace, chemical processing, marine engineering, pollution-control equipment, and nuclear reactors.

In what form is Inconel 718 Available at Micrometals

  • Sheet
  • Plate
  • Bar
  • Wire

Chemical Composition, %

Ni Fe Cr Cu Mo Nb C Mn
50.00-55.00 Remainder 17.00-21.00 .30 max 2.80-3.30 4.75-5.50 .08 max .35 max
P S Si Ti Al Co B
.015 max .015 max .35 max .65-1.15 .20-.80 1.00 max .006 max

ASTM Specifications

Sheet/Plate Bar Wire
B670 B637 -

Mechanical Properties 
Typical room temperature properties, 1800°F annealed condition

Ultimate Tensile Strength, psi .2% Yield Strength psi Elongation % Hardness Rockwell B
135,000 70,000 45 100