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Alloy 718 (UNS N07718, 2.4668)

General information

Alloy 718 is a precipitation-hardening nickel-chromium-iron superalloy, characterized by high strength, excellent corrosion resistance, and exceptional weldability up to 704°C (1299°F). It is widely used in aerospace, oil & gas, and industrial high-temperature applications.

Applications

Industrial

Aerospace, Power Generation, Oil & Gas, Chemical Processing, Automotive & Industrial, etc.

Features

High temperature strength

Outstanding creep and rupture strength up to 704°C.

Weldability

Excellent resistance to post-weld cracking.

Corrosion resistance

Good oxidation resistance up to 980°C; resistant to sour gas (H2S / CO2 ) environments.

Material

Alloy 718 / UNS N07718 / 2.4668

Surface

Bright annealed / Polishing

Package

Wooden case / Plywood case

Chemical composition (Nominal) %

Grade C Si Mn P S Cr Ni Cu
Alloy 718 0.08 0.35 0.35 0.015 0.015 17-21 50-55 0.3
Mo Ti Nb B Co Al
2.8-3.3 0.65-1.15 4.75-5.5 0.006 1 0.2-0.8

Physical properties

Density 8.19 g/cm3 (0.306 lb/in3)
Hardness 36-44 HRC

Heat treatment

Recommended Solution Treatment Precipitation Hardening Treatment
1700 to 1850°F (924 to 1010°C), hold 1/2 h min, cool at rate equivalent to air cool or faster. 1325 ± 25°F (718 ± 14°C), hold at temperature for 8 h, furnace cool to 1150 ± 25°F (621 ± 14°C), hold until total precipitation heat treatment time has reached 18 h, air cool.

Flat and round bar

Key standards

AMS 5662, 5663, 5664, 5596, 5832 | ASTM B637, B670 | ASME SB637

Mechanical properties

Heat Treatment Tensile Strength, min, psi (MPa) Yield Strength, min. (0.2% offset), min, psi (MPa) Elongation in 2 in. (50 mm) or 4D, min, % Reduction of Area, min, %
Solution + precipitation harden 185000 (1275) 150000 (1034) 12 15