Nanocomposite Sm2Co17/Co permanent magnets by mechanical alloying

Mechanically alloyed magnets SmCox (x = 6.0-11.0) have been prepared using starting materials of commercial SmCo5 and Co powders. X-ray diffraction data indicate that the equilibrium Sm2Co17 phase can be achieved in a nanocomposite Sm2Co17/Co system at x=8.5-11.0, while a Sm2Co17/SmCo5 structure occurs at x=6.0-8.0. The best magnetic properties obtained at x=10.0 are as follows: (BH)(max)=10.2 MGOe, B-r=9.4 kG, H-c=4.0 kOe, and S=0.82. Wohlfarth's remanence analysis indicates that the high remanence can be attributed to the intergranular interaction between neighboring cobalt and Sm2Co17 grains. (C) 1996 American Institute of Physics.