Soft magnetic properties of (Fe-B)85Nd15amorphous films

Soft magnetic properties were found in amorphous (FexB1-x)85Nd15films made by sputtering with the composition corresponding to permanent magnets of NEOMAX (Fe77B8Nd15), where the coercivity is less than a few Oe and the in-plane uniaxial magnetic anisotropy constant is less than 10³erg/cc. Such soft magnetic properties of films could be a key to understanding the high coercivity mechanism in melt-spun and sintered permanent magnets of these alloy systems with the light rare-earths. An annealing experiment shows that the uniaxial anisotropy decreases from 10³to 10²erg/cc, whereas the coercivity increases as the annealing temperature increases from 100 to 160°C for 2 hr.