Tremendous enhancement of magnetic performance for Sm(CoFeCuZr) magnet based on multiscale copper redistribution

Microstructure and magnetic properties were studied for the commercial Sm(CoFeCuZr)z magnets before after post annealing treatment. The results show that phases composition orientation of magnet do not change treatment, but substantial redistribution Cu element within multiscale (the microscale crystal grain nanoscale cellular structure) is observed simultaneously. In detail, along with redistribution, thickness Cu-rich Sm(Co,Cu)5 cell boundary becomes thinner, concentration in increases sharply. pinning field domain walls corresponding coercivity increase remarkably slight remanence maximum energy product loss, overall performance (BH)max (MGOe)+Hcj (kOe) by 54.3% as a result. Moreover, thermal stability improves well. On other hand, Cu-lean phenomenon was region, triggering to reversal process slightly undermining squareness demagnetization curve magnet.