Effect of the milling time on the magnetic properties of powder compositions of the Sm2Fe17Nx intermetallic compound and an Nd–Fe–B alloy

Resumo

The effect of the wet milling time on the magnetic properties of powder compositions consisting of the hard magnetic Sm₂Fe₁₇N_x (x = 2.9–3.0) nitride and a rapidly quenched Nd_9.6Fe_76.3Co_4.3Zr_3.4B_6.4 (at %) alloy, which are taken in different mass proportions, is studied. The compositions containing no more than 20 wt % alloy are found to exhibit a substantial increase in the magnetic characteristics as compared to those of the nitride. It is shown that the determining effect on the coercivity is related to the degree of structural imperfection of Nd–Fe–B powders, whereas the specific remanent magnetization and the specific magnetization in a field of 2 T are determined by the corresponding characteristics of the alloy. The optimum composition and efficient treatment conditions for powder mixtures are determined.