The microstructure and magnetic characteristics of Sm(CobalFe0.1Cu0.09Zr0.03)7.24 high temperature permanent magnets

Abstract Two kinds of Sm(Co bal Fe 0.1 Cu 0.09 Zr 0.03 ) 7.24 high temperature magnets were fabricated by a traditional powder metallurgical technology with different annealing processes. A record of maximum energy product of 94.73 kJ/m 3 at 773 K with a high intrinsic coercivity of 652.72 kA/m was made. Based on the theoretical and experimental results, it was found that the temperature coefficient of the coercivity was strongly influenced by the variation of the Curie temperature of the cell wall phases and the domain wall energy ratio between cell and cell wall phases at 0 K. The characteristic properties originate from the element redistribution between SmCo 5 /Sm 2 Co 17 interfaces while annealing.