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.

Tensile Properties of Solution-annealed 718 at Room Temperature

Ultimate Tensile Strength Yield Strength Elongation
ksi MPa ksi MPa %
Sheet 126.3 871 60.7 419 46.7
Plate 124.3 857 57.3 395 49.0

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.