HIGH-COERCIVITY SM-2(FE,AL,MO)(17)C-1.5 RIBBONS WITH ADDITION OF MO

The effects of Mo additions on the structure and magnetic properties o f Sm2Fe(15.5-x)MoxAl1.5C1.5 alloys have been investigated by means of x-ray diffraction (XRD), scanning electron microscopy, transmission el ectron microscopy, and magnetic measurements. The XRD analyses show th at as-cast alloys consist mainly of a 2/17-type carbide and a consider able amount of alpha-Fe. Rapidly quenched, the Mo-containing alloys fo rm a nanocrystalline structure with an average grain size of 35-50 nm, while the amount of the alpha-Fe phase is greatly decreased. The magn etic hardening of the Mo-containing alloys can be achieved by direct q uenching. A coercivity exceeding 1.35 T is obtained for the Sm2Fe14.9M o0.6Al1.5C1.5 ribbon spun at 40 m/s. These results reveal that the add ition of Mo is effective in improving the coercivity. (C) 1998 America n Institute of Physics.