Bulk‐hardened Sm‐Co‐Cu‐Fe 2:17 magnets

Sm(C00.87Cu0.13)z alloys were prepared with 7.2⩽z<8. Homogenization heat treatment yielded single‐phase 2:17 material for z≳7.2. For z=7.8 some of the Co was substituted by Fe. Homogenized alloys remained single phase for up to 15% Co substituted. Remanence values BR up to 12.1 kG were reached. Coercive fields IHC of 4 kOe were achieved by means of a low‐temperature heat treatment. The magnetization process implies that pinning of the Bloch walls is responsible for the coercivity mechanism.