Inconel 718

Synopsis

Inconel 718, a large strength, thermal resistant nickel alloy, is primarily used in the aircraft industries. It is a precipitation hardening alloy that keeps its resistance, strength, oxidation, and ductility while in the most extreme environments. This performance must be kept constant during long periods at high temperatures, which is fulfilled by the Inconel series. It is used in many industries for their critical applications including aerospace and oil and gas.


Resistance

Inconel 718 has beneficial protection to atmospheric decay and corrosion at climates within the nickel alloys strength space. It has somewhat favorable weldability, formability, and exceptional low temperature properties comparable to other PH nickel alloys.


Processing

Inconel 718 requires particular heat treatment solutions, hinging on what the intended final need is for the component – the approach is particular for either attaining the greatest flex/tensile strength and force-fracture properties for extreme temperature operations, or for augmenting the benefits for use at room or freezing temperatures. The 3 main conditions of Inconel 718 are AMS 5662, AMS 5663, and NACE MR0175/0103. AMS 5662 is considered the annealed condition and is the precursor to AMS 5663. Inconel 718 NACE calls out for a different chemistry and a hardness range set from 32 – 40 HRC. Each condition has specific uses depending on the application.


Physical Properties:

Condition
Tensile Yield Enlongation Reduction
of Area
Hardness
NACE 150KSI 120KSI 20% 35% 32-40 HRC
AMS5663 185KSI 150KSI 12% 15% 331 BHN min

Applications

  • Aerospace
  • Oil and Gas
  • Valves
  • Chemical
  • Jet Engines
  • Fasteners
  • Aircrafts
  • 3D Printing
  • Gas Turbine Engines
  • Cryogenic Tanks

Benefits

  • Excellent corrosion and oxidation resistance in harsh environments
  • Very strong with high mechanical properties
  • Good durability and ductility
  • Significant volume of iron, diminishing Inconel 718's cost per kg while enhancing its strength with precipitation hardening.
  • Inconel 718 keeps robust resistance to corrosion up to 1000°C.
  • Nickel alloys combat chloride-ion stress-corrosion cracking and protects from corrosion in many oxidizing compounds