AMS 5662
Nickel Alloy, Corrosion and Heat-Resistant, Bars, Forgings, and Rings, 52.5Ni - 19Cr - 3.0Mo - 5.1Cb - 0.90Ti - 0.50Al - 18Fe, Consumable Electrode or Vacuum Induction Melted, 1775 °F (968 °C) Solution Heat Treated, Precipitation-Hardenable
Material specification for Inconel 718 (UNS N07718) bars, forgings and rings, consumable-electrode or vacuum-induction melted, supplied solution heat treated at about 1775 °F (968 °C) and precipitation hardenable by the user.
What AMS 5662 specifies
AMS 5662 is the "solution treated" form of the standard Inconel 718 bar and forging specification: the mill solution treats the product at 1700–1850 °F (925–1010 °C) — nominally 1775 °F (968 °C) — and cools it rapidly, so it arrives soft enough to machine and is aged by the part manufacturer. The specification controls composition (50–55 Ni, 17–21 Cr, 2.8–3.3 Mo, 4.75–5.5 Nb, 0.65–1.15 Ti, 0.2–0.8 Al, balance Fe), melting practice, grain size and macrostructure, and requires a capability (heat-treat response) test: samples from each lot are aged per the AMS 5663 cycle — 1325 °F (718 °C) for 8 h, furnace cool to 1150 °F (621 °C), 18 h total — and must reach AMS 5663 properties: 185 ksi (1275 MPa) tensile, 150 ksi (1035 MPa) yield, 12 % elongation, 331 HB minimum, and 23 h stress-rupture life at 1200 °F (649 °C) under 100 ksi (690 MPa). Parts are aged under AMS 2774.
Tests and the drawing call-out
Tests the document imposes
- Heat-treat response: tensile per ASTM E8/E8M after ageing per the AMS 5663 cycle
- Stress-rupture per ASTM E139 at 1200 °F / 100 ksi, 23 h minimum with 4 % elongation, on aged samples
- Hardness per ASTM E10 / E18 after ageing (331 HB / 36 HRC minimum)
- Grain size per ASTM E112 and macrostructure
- Chemical analysis; ultrasonic inspection per AMS-STD-2154 when specified
How to cite it
Drawing call-out
MATERIAL: INCONEL 718 BAR PER AMS 5662; PRECIPITATION HEAT TREAT PER AMS 5663 / AMS 2774 AFTER MACHININGAngle brackets mark the choices the drawing must make; every finish page shows a completed example.
Heat treatments specified to AMS 5662
| Treatment | Role | Cost |
|---|---|---|
Age (Inconel 718) is a precipitation-hardening condition for Inconel 718 (UNS N07718) and Alloy 718 AM. | Related | $$$$ |
AMS 5662 — frequently asked
What is the difference between AMS 5662 and AMS 5663?
Same alloy, melt practice and grain controls; 5662 is delivered solution treated only, to be aged by the user, while 5663 is delivered solution treated and aged. Machine-then-age parts are bought to 5662; small parts machined from fully hardened stock are bought to 5663.
Why machine 718 before ageing?
Ageing raises hardness to 36–44 HRC and roughly doubles the yield strength; in the solution-treated state the alloy is markedly softer and tool life is much better. The age causes only a small, predictable dimensional change, so parts are finished before ageing with an allowance from the heat treater's data.
What does "consumable electrode or vacuum induction melted" mean for me?
Both are clean-melting routes (VIM plus VAR or ESR) that keep nitrogen, oxygen and inclusion counts low enough for the fatigue and stress-rupture requirements; air melting is not permitted. Certifications list the melt route and the heat number that ties the bar to its capability test.
Should I use AMS 5662 or AMS 5664?
AMS 5664 uses a higher solution temperature (about 1950 °F / 1065 °C) that coarsens the grain for better creep and stress-rupture at 1200–1300 °F at the cost of tensile and fatigue strength; 5662 (1775 °F) gives the fine-grain, high-strength condition used for shafts, fasteners and most structural parts.
AMS 5662 is copyrighted by SAE International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗