Microstructural Evaluation of Nd-Fe-B Strip Cast Alloys

In this investigation, we evaluated the microstructure of SC alloys using SEM, TEM and XRD. The composition of SC alloys was Nd14.4Fe79.6B6.0 and Nd10.4Dy3.5Fe80B6.1, and the SC alloys show petal-shape or dendritic structure at the wheel surface or the free surface, respectively. Grain size distribution is broad at the wheel surface and the microstructure is changed at the distance of around 50 μm from the wheel surface. XRD analyses are consistent with the results. Average interval of R-rich (R: rare earth) lamella structure in Nd10.4Dy3.5Fe80B6.1 and Nd14.4Fe79.6B6.0 SC alloys are 3.9 μm and 3.7 μm, respectively.