Alloy 718 / 2.4668
Alloy 718 (2.4668) has a very good creep resistance. Besides the good short-and long-term mechanical properties – especially at low temperatures -, it has a high fatigue strength and offers a very good weldability in the application of arc and resistance welding processes. Alloy718 is not susceptible to weld cracking. Alloy 718 is an age-hardenable alloy. By heat treatment an increase in strength can be achieved.
Material Data Sheet
| Material Designation | 2.4668 |
|---|---|
| Alloy | Alloy 718 |
| EN Material Symbol | NiCr19Fe19Nb5Mo3 |
| UNS | N07718 |
| DIN EN | 17744 |
| AMS | 5662 |
| AMS | 5663 |
Main fields of application of alloy 718
Alloy 718 was originally developed for the aerospace industry, and is now not only used in engines, gas turbines, or other components of the aircraft industry, but also in nuclear reactors, springs and high-strength bolts. In the oil and gas industry Alloy718 is also very popular because of its corrosion resistance and strength.
Chemical composition of alloy 718
| C | Si | Mn | P | S | Cr | Mo | Ta |
|---|---|---|---|---|---|---|---|
| % | ≤ % | ≤ % | ≤ % | ≤ % | % | % | % |
| 0-0.08 | 0-0.35 | 0.035 | 0-015 | 0-0.015 | 17.0-21.0 | 2.8-3.3 | 0-0.05 |
| Nb | Ni | Al | Co | Cu | Fe | Ti | B |
| % | % | % | ≤ % | ≤ % | % | % | ≤ % |
| 4.75-5.5 | 50.0-55.0 | 0.2-0.8 | 0-1.0 | 0-0.3 | rest | 0.65-1.15 | 0-0.006 |
Characteristics of alloy 718
| Temperature Range | High Temperature Range / Material for Wet Corrosion |
|---|---|
| Density | 8.2 g/cm³ |
| Melting Range | 1260 - 1340°C |
| ISO-V notch impact toughness at -59°C | Across < 47 J/cm² |
| lengthwise < 71 J/cm² |
Filler metal (for welding with alloy 718)
Alloy 718 is recommended itself as filler material.