Description: AFM 718 is used for welding nickel-chromium-niobium-molybdenum alloy (718) to
itself using the GTAW processes. AFM 718 is a precipitation hardenable
nickel-base alloy designed to display exceptionally high yield, tensile and
creep-rupture properties at temperatures up to 1300¡ÆF (704¡ÆC). The sluggish
age-hardening response of AFM 718 permits annealing and welding without
spontaneous hardening during heating and cooling. AFM 718 has excellent
weldability when compared to the nickel-base superalloys hardened by aluminum
and titanium.
Chemical Composition Requirements for Undiluted Weld Metal: |
| (AL) |
Aluminum |
0.20 to 0.80 |
| (B) |
|
0.003 |
(C) |
Carbon |
0.08 |
| (Cr) |
Chromium |
17.0 to 21.0 |
| (Cu) |
Copper |
0.30 |
| (Fe) |
Iron |
BAL |
| (Mn) |
Manganese |
0.35 |
(Mo) |
Molybtenum |
2.80 to 3.30 |
| (Ni) |
Nickel |
50.0 to 55.0* |
| (Nb + Ta) |
Nickel |
4.75 to 5.50 |
(P) |
Phosphorus |
0.015 |
(S) |
Sulfer |
0.015 |
| (Si) |
Silicon |
0.35 |
| (Ti) |
Titanium |
0.65 to 1.15 |
|
Vanadium |
0.50 |
* Includes incidental cobalt
All values are considered maximum, unless other-wise noted.
Typical As-Welded Tensile Strengths (min.):
- Tensile Strengths, psi - 165,000*
- MPa - 1140* *
Age-hardened condition: Heat treated at 1325¡ÆF (718¡ÆC) for 8 hours, then furnace cooled to 1150¡ÆF (620¡ÆC) at 100¡ÆF (56¡ÆC) per hour, held for 8 hours, then air cooled.
Standard Sizes: 36¡± TIG-1/16 (1.6), 3/32 (2.4), 1/8 (3.2), & 5/32 (4.0) 30# spools-.035 (1.0), .045 (1.2), & 1/16 (1.6)
|
