Glass transition and crystallization process of hard magnetic bulk Nd60Al10Fe20Co10 metallic glass

Glass transition and crystallization process of bulk Nd60Al10Fe20Co10 metal lic glass were investigated by means of dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) a nd scanning electronic microscopy (SEM). It is shown that the glass transit ion and onset crystallization temperature determined by DMTA at a heating r ate of 0.167 K/s are 480 and 588 K respectively. The crystallization proces s of the metallic glass is concluded as follows: amorphous alpha-->alpha' metastable FeNdAl novel phase -->alpha' + primary delta phase-->primary de lta phase + eutectic delta phase Nd3Al phase + Nd3Co phase. The appearance of hard magnetism in this alloy is ascribed to the presence of amorphous ph ase with highly relaxed structure. The hard magnetism disappeared after the eutectic crystallization of amorphous phase.