Micromagnetic and microstructural studies of NdFeB by TEM

Abstract

Transmission electron microscopy has been used to study the magnetic and physical microstructure of thinned samples of NdFeB. Various compositions of sintered material and nanocrystalline melt-spun ribbon have been studied. The mean grain size in the materials ranges from 3 μm in the sintered material down to 20nm in the ribbon and this has a pronounced effect on the domain structures supported. Details of the magnetisation distribution both within grains and around boundaries are given and these are discussed in terms of the observed bulk magnetic properties.