AMS 5758 is a sub-type specification of Cobalt M35N, a cobalt-based alloy that is characterized by an ultra-high-strength of 260 ksi to 300 ksi (1790 mPa to 2070 mPa). This specification has a high percentage of cobalt, nickel, chromium, and molybdenum.
The use of these elements gives AMS 5758 excellent stress corrosion cracking, pitting corrosion resistance, and crevice corrosion resistance. Other qualities of this specification include good ductility, excellent toughness, and excellent embrittlement resistance in cryogenic temperatures. AMS 5758 is non-magnetic. Tech Steel & Materials offers AMS 5758 as a bar.
Thanks to the combination of ultra-high-strength and outstanding corrosion resistance in multiple environments, AMS 5758 is used for the manufacturing of parts in many different fields. The Aircraft and Aerospace industries use it for springs and leading-edge strips. Autosport companies use it for valves and springs in racing engines.
AMS 5758 bars are produced using vacuum induction melting and consumable vacuum arc re-melting processes. The bars are then solution heat-treated at 1900° F to 1925° F and aged for 4 to 8 hours. AMS 5758 can be additionally strengthened using traditional cold-working methods, such as extruding, drawing, rolling, and swaging, or any combination of them. An additional aging process can be applied to further strengthen the part.