Mechanism of coercive force in FeCrCo alloys

To further the understanding of the origin of the coercive force in FeCrCo alloys, the average magnetization <Ms>, coercive force (Hc) and anisotropy (Ku) were measured as a function of temperature. An alloy with composition 28 wt% Cr-10.5 wt% Co-Fe was investigated. Optimum magnetic properties of these alloys are derived by a heat treatment process in which the alloy spinodally decomposes into two phases each with a different saturation magnetization. If the alloy is heat treated in a magnetic field to produce elongated precipitate particles, the resulting anisotropy is proportional to the square of the difference in the magnetizations of the two phases and the magnetocrystalline anisotropy which arises from any possible crystallographic texture. Analysis of measurements of <Ms>, Kuand Hcindicate that the predominant contribution to the coercive force is from the square of the difference in the magnetizations of the two phases and not from the magnetocrystalline anisotropy.