Differences of element distribution between free and wheel side surface of NdFeB/α-Fe ribbons

The ribbons of NdFeB/α-Fe composite alloy were prepared by melt spinning and post crystallizing technique. The element distributions and phase component of both surfaces of as-spun ribbons were measured by energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). Because of the centrifugation, a segregation of B, Fe, and Nd concentrations was observed at the cross section. After crystallizing annealing, the element concentration segregation still existed in the as-crystallized ribbons. Due to the segregation of B, Fe, and Nd, the B-rich phase was observed near the wheel side surface. The B-rich phase may deteriorate the magnetic property of NdFeB/α-Fe composite alloy.