Phase analysis of nanocomposite magnetic materials by electron energy lossspectrometry

EELS (electron energy loss spectrometry) in the transmission electron micro scope (TEM) was used to determine the composition of a nanocrystalline magn etic specimen. The relative amounts of the hard magnetic phase Nd2Fe14B and the soft magnetic phase Fe3B at the point of measurement was measured by s tandard EELS quantification. In order to determine the structure of Fe3B pr esent, the fine structure of the boron K-ionisation edge was analysed. Comp arison of the experimental spectra with simulations of the fine structures based on the TELNES extension of the WIEN97 program package, a full potenti al linearised augmented plane wave approach to the calculation of electroni c structure in crystals, shows that the tetragonal form of Fe3B is predomin ant.