Magnetic properties of Er2Co17-xSix compounds

The structure and magnetic properties of Er2Co17-xSix compounds with Si concentrations up to 2 were investigated by X-ray diffraction and magnetic measurements. All compounds show easy-axis anisotropy at room temperature. With increasing Si concentration, the spontaneous moment and the Curie temperature decrease strongly, while the anisotropy field at 300 K increases modestly. The high-field magnetization was measured on powder particles free to rotate in the applied field, to derive the intersublattice-molecular-field coefficient nErCo and the exchange-coupling constant JErCo. The strength of the Er-Co exchange coupling is not much affected by Si substitution