THE EFFECTS OF NITROGEN UPTAKE ON Y2FE14B - STRUCTURAL, MICROSTRUCTURAL AND MAGNETIC CHARACTERIZATIONS

The compound Y2Fe14B has been subjected to reaction with N2 at different gas pressures and different temperatures. X-ray powder diffraction patterns, microstructural investigations made by scanning electron microscopy or magnetic measurements do not confirm the formation of a new nitride compound with the formula Y2Fe14BNx (x < 1). All these experiments are consistent with a decomposition of the starting alloy after reaction into other types of nitrides and borides. A critical analysis of the results described in previously published papers claiming the formation of a new nitride is given and it is shown that all the measured physical properties are in agreement with the hypothesis of the decomposition of the sample.