Magnetic and mechanical properties in crystallized amorphous Fe-Co-Ni-Al based ribbons

The technique of crystallization of amorphous alloys has been applied to (Fe,Co,Ni,Cu)100-x-yAlxMeyalloys (Me=B, C, Si, P) in order to develop mechanically workable hard magnetic materials. The alloys with and can be quenched into ductile amorphous or semi-amorphous ribbons using a single roller method. As-prepared ribbons have no hard magnetic properties before annealing. Controlled crystallization of the ribbons results in metastable multiphase microstructure and develops hard magnetic properties. The coercive forces obtained depend strongly on glass forming elements. Of the elements investigated, boron is the most effective for magnetic hardening. (Fe59Co26Ni15)73Al7B20ribbon, which is initially semi-amorphous, has the minimum bending diameter of 1 mm and the tensile strength of 100 kg/mm²before crystallization annealing, and showsiHcof 450 Oe, Br of 7 kG, and (BH)maxof 1.2 MGOe after crystallization.