The Magnetic Susceptibility of Alloys Below the Percolation Threshold

Within the theory of random interaction fields, the possibility of determining the Curie point and the paramagnetic Curie point corresponding to the appearance of short-range order is shown. In ferromagnetic alloys, there is a concentration range in which the long-range order is destroyed, but the short-range order persists. This leads to the appearance of a cluster glass phase, which is characterized by a time dependence of the magnetic susceptibility and the appearance of viscous magnetization. For an AuFe alloy as an example, the behavior of the initial magnetic susceptibility as a function of temperature and concentration is studied and compared with experimental data.