MAGNETIC-PROPERTIES OF (LR(X)SM(1-X))(2)(FECO)(17)N-2-DELTA ZN BONDEDMAGNETS (LR-LA, CE)

(LR(x)Sm(1-x))(2)(Fe1-yCoy)(17) alloys (LR = La, Ce; x = 0, 0.1, 0.3, 0.5, 0.8, and 1; y = 0, 0.2) were prepared by are melting, homogenizat ion and pulverizing. A single-phase Th2Zn17-type structure is sustaine d for the whole range of x for Ce, but only for x<0.35 for La substitu tion (y = 0, 0.2). The alloys were then nitrogenated under flowing nit rogen to give (LR(x)Sm(1-x))(2)(Fe1-yCoy)(17)N-2-delta(delta = +/-0.1) alloys. These were pulverized again and mixed with 16.7 wt.% Zn powde r, after which they were die pressed then sintered at 450 degrees C. T he bonded magnets have a remanence of 4.9-5.6 kG (at about 80% of true density), a coercivity of 2.8-3.9 kOe and a (BH)(max) value of 3.3-3. 5 MG Oe, depending on LR and x, but are independent of y. Low density, and uneven and low nitrogen content are the main reasons for unsound magnetic properties. There is much room for improvement in the magneti c properties, by optimizing the nitrogenation and densification. The L a- or Ce-substituted Sm-2(Fe,Co)(17)N-2-delta alloys show potential in applications as low price resin-bonded magnets.