Effect of Zr, V, Nb, Mo, and Ta substitutions on magnetic properties and microstructure of melt-spun SmCo 5 magnets

We have investigated effects of metal substitutions on the magnetic properties and microstructure of melt-spun Sm-Co-Cu-Fe-M (M = Zr, V, Nb, Mo, Ta) magnets. We prepared melt-spun ribbons with compositions of Sm(Co Cu ) Fe M ( = 0.1-0.5, = 0-0.43, M = Zr, V, Nb, Mo, Ta). For compositions of Sm(Co Cu ) Fe ( = 0.1-0.5), coercivity increased with increasing of annealing temperature, and a high coercivity of 17.6 kOe was obtained at a Cu content of = 0.3. The coercivity was found to increase with increasing melting point of the substitution element. A high coercivity of 24.5 kOe was obtained for a composition of Sm(Co Cu ) Fe Ta .