AMS 5655 is a sub-type specification of Stainless Steel 422. This high-alloy steel is characterized by martensitic crystal structure, which gives it good mechanical properties, such as excellent creep-rupture and resistance to scaling at temperatures up to 1200° F (649° C).
Thanks to the high concentration of Chromium, AMS 5655 has good resistance to corrosion and oxidation. This specification of Stainless Steel 422 is available as bar, forging and welding wire.
AMS 5655 is widely used in the aerospace industry for manufacturing of high-temperature bolting, valves, and valve trim, and also in steam turbines for buckets and blades.
This alloys if fairly easy to machine, but special care still must be applied to avoid galling if sharp tools are used. Parts made of AMS 5655 should be welded using only the welding wire of the same specification. Even then, preheating is mandatory in order to prevent cracking, followed by a post-weld stress relief at 1100 – 1400° F (590 – 760° C) for 4 hours.
AMS 5655 bars and forgings can be heat treated using standard heat treatments, such as hardening, tempering, and annealing. Depending on the wanted qualities, different combinations of these heat treatments are recommended.