Saturation magnetization and anisotropy fields in the Sm(Co1−xCux)5 phases

The magnetic characteristics of high‐anisotropy Sm(Co1−xCux)5 phases are determined experimentally at 300 K in the range x<0.6. The saturation magnetization Ms decreases and vanishes for SmCo2Cu3. Identical behaviors of Ms and Curie temperature TC versus x are observed in the range x<0.6. For significant Cu substitution rate (x≳0.35), the decrease of the anisotropy field (HA) when x increases is strong. For lower Cu contents, huge values of anisotropy fields make difficult the accurate determination of the substitution effect. The first anisotropy constant K1 is calculated using the available values of HA and Ms. A linear decrease of K1 is observed from SmCo5 to SmCo2Cu3.