Cobalt-iron alloy 1J22 (Permendur) is a soft magnetic alloy with the highest saturation induction of any common soft magnetic material, and is used for lightweight, high-performance motors, transformers, and electromagnets.
1J22 (Permendur, Hiperco 50) is a soft magnetic iron-cobalt-vanadium alloy with the highest saturation induction of any common soft magnetic material. That lets it carry more flux in smaller, lighter parts, and its Curie point above 900 °C keeps it working at high temperatures.
Trade-offs include that it is harder to fabricate than other iron alloys, and both its magnetic performance and its strength depend on a final heat treatment.
1J22 is a strong choice for electromagnet pole pieces, relay parts, small rotors, and transducer components.