Permenorm

Permenorm

 

a low-nickel Permalloy that consists of approximately 50 percent nickel and 50 percent iron. The saturation magnetization and magnetic permeability μ of Permenorms, which are soft-magnetic materials, are characteristically high. Permenorms were developed in Germany during World War II. Typically, they have a saturation magnetization of 1.5–1.6 tesla, an initial magnetic permeability μα ≥ 3,500, a maximum magnetic permeability μmax ≥ 35,000, and a Curie point of 500°C. The value for μa can be raised to 10,000 by imparting a certain grain orientation to the alloy, a procedure that is sometimes performed in combination with additional thermal treatment under an applied magnetic field; these techniques can also be used to produce a Permenorm with a rectangular hysteresis loop and with a μmax > 100,000.

Permenorms are used for producing transformer cores, choke coils, and electrical relays. The equivalent of Permenorms in the USSR are alloys that are manufactured under the names 50N, which contains 50 percent Ni, and 50 NP, which contains 50 percent Ni and is characterized by a rectangular hysteresis loop.

REFERENCES

Heck, C. Magnitnye materialy i ikh tekhnicheskoe primenenie. Moscow, 1973. (Translated from German.)
Reinboth, H. Technologie und Anwendung magnetischer Werkstoffe, 3rd ed. Berlin, 1970.