HAYNES® 718 alloy has very good forming and welding characteristics. It may be hot-worked at temperatures in the range of about 1700-2100°F (925-1150°C) provided the entire piece is soaked for a time sufficient to bring it uniformly to temperature. Initial breakdown is normally performed at the higher end of the range, while finishing is usually done at the lower temperatures to afford grain refinement.
As a consequence of its good ductility, 718 alloy is also readily formed by cold-working. All hot- or cold-worked parts should normally be annealed at 1700 to 1850°F (925 to 1010°C) and cooled by air cool or faster rate before aging in order to develop the best balance of properties.
Cold-work Hardness
| % Cold-work |
Average Hardness HRBW/ C |
| 0 |
92.4 HRBW |
| 10 |
27.2 HRC |
| 20 |
33.6 HRC |
| 30 |
36.9 HRC |
| 40 |
38.3 HRC |
| 50 |
39.2 HRC |
HRBW = Hardness Rockwell “B”, Tungsten Indentor.
HRC= Hardness Rockwell "C".
Hardness and Grain Size
| Form |
Hardness, HRBW |
Typical ASTM Grain Size |
| Sheet |
94 |
6 - 8
|
| Plate |
93 |
5 - 8
|
All samples tested in solution-annealed condition.
HRBW = Hardness Rockwell “B”, Tungsten Indentor.