Domain structure of hard magnetic NdAlFeCo bulk metallic glass

Magnetic domain structure of hard magnetic Nd60Al10Fe20Co10 bulk metallic g lass (BMG) has been studied by using magnetic force microscopy. In the magn etic force images it Is shown that the exchange interaction type magnetic d omains with a period of about 360 nm do exist in the BMG, which is believed to be associated with the appearance of hard-magnetic properties in this s ystem. As the scale of the magnetic domain is much larger than the size of the short-range ordered atomic clusters existing in the BMG, it is believed that the large areas of magnetic contrast are actually a collection of a g roup of clusters aligned in parallel by strong exchange coupling interactio n. After fully crystallization, the BMG exhibits paramagnetism. No obvious magnetic contrast is observed in the magnetic force images of fully crystal lized samples, except for a small quantity of ferromagnetic crystalline pha se with low coercivity and an average size of 900 nm.