718

Inconel 718

Category: .


Product Description

Inconel 718

Inconel 718

Inconel 718 Alloy is a precipitation-hardenable Ni-Cr-Fe alloy containing significant amounts of Nb & Mo as well as lesser amounts of Al+Ti. The alloy has good ductility in the annealed condition and high strength up to 700 ℃.

  • good fabrication characteristics in the annealed condition
  • good tensile, fatigue and creep-rupture strengths
  • high-temperature strength up to 700℃
  • good oxidation resistance up to 1000 ℃
  • excellent mechanical properties in cryogenic environments
  • excellent corrosion resistance at high and low temperatures and good resistance to stress-corrosion cracking and pitting corrosion
  • good weldability by arc and resistance welding processes without susceptibility to post-weld cracking

Density: 8.19

Corrosion resistance

The high chromium and molybdenum contents of Inconel 718 Alloy impart excellent resistance to uniform and localized corrosion, such as pitting in many media at both high and low temperatures. The chromium also enables it to withstand chloride-ion stress-corrosion cracking which makes it an excellent alloy for service in oil and sour gas (H2S containing) environments as well as seawater.
Inconel 718 Alloy is generally only used for applications not exceeding 700 ℃. However, oxidation resistance up to 1000 ℃ is particularly high and comparable to that of other gamma-prime strengthened superalloys

Applications of Inconel 718:

Due to its high-temperature strength up to 700℃, excellent corrosion resistance and ease of fabrication Inconel 718 Alloy finds applications in many fields. Initially it was used as a turbine disk material in aircraft jet engines. Here resistance to creep and stress rupture was most important.
Because of its properties, fabricability and cost effectiveness it has since gained wider acceptance. To-day applications vary from highly stressed rotating and static components in gas turbines and rocket engines to high-strength bolting, springs and fasteners, components in nuclear reactors and space vehicles as well as high-temperature tooling for extrusion, of for example copper, and shearing. Another more recent important application involves pump shafts and other highly stressed well head and downhole components in offshore
and marine engineering. Particularly useful is the alloy for drilling equipment in sour (containing H2S, CO2 and chlorides) oil and gas wells.

Chemical composition

Ni Cr Fe C Mn Si Cu Mo Co Nb Al Ti B P S
min(%) 50.0 17.0 bal. 2.80 4.75 0.20 0.65
max(%) 55.0 21.0 0.08 0.35 0.35 0.30 3.30 5.50 0.80 1.15 0.006 0.015 0.015

Mechanical properties

Condition Yield Strength(Mpa) Tensile Strength(Mpa) Elongation(%) Reduction of Area(%) Hardness(HB)
ASTM Min Value Solution Annealed + Aged 1034 1275 12 15 331
Typical Values at RT Solution Annealed + Aged 1176 1343 17 382

International Specification Comparison chart

Material Round Bar Plate Pipe
Seamless Welded
ASTM UNS
N07718
B673 B670
ASME SB673 SB670
JIS NCF718 H4553 G4901 H4552
DIN 2.4668 17752 17750 17751

 

Product: Sheet, Coil, Pipe, Bar, Wire and Forgings