M. Febri et al., A NEW METHOD OF NITROGENATION OF RE-TM ALLOYS VIA CHEMICAL-REACTION WITH SODIUM-AZIDE AS AN OXYGEN-FREE NITROGEN-SOURCE, Journal of magnetism and magnetic materials, 158, 1996, pp. 103-104
Y2Fe17 and other RE-Fe-based compounds have been successfully nitrogen
ated by heating mixtures of powdered alloy with sodium azide at temper
atures between 300 and 450 degrees C. The high nitrogenation power of
NaN3 seems to come from its low decomposition temperature and an impro
ved nitrogen diffusion rate through the particle surfaces cleaned by s
odium.