Magnetic Susceptibility of Intermetallic Compounds in a REM—Al System at High Temperatures

The Faraday method is used to study for the first time the temperature dependence of the magnetic susceptibility of intermetallic compounds of rare-earth metals (REM = Gd, Dy, Ho, and Er) with aluminum in a wide temperature interval from room temperature to 1700°C encompassing their solid state, melting process, and liquid state. It is established that for all examined compounds, except the Gd–Al system, the dependence χ(T) is linear. It is described by the modified Curie–Weiss law for solid and liquid compounds of the Gd–Al system. The Curie paramagnetic temperature θp, the Curie–Weiss constant C, the temperature-independent susceptibility component, and the effective magnetic moments μeff per REM atom are calculated on a computer by the least-squares method based on the dependence χ–1(T). The indirect exchange interaction parameter of the examined compounds is also calculated semi-empirically.