The role of grain boundaries in the coercivity of hydrogenation disproportionation desorption recombination processed Nd–Fe–B powders

Abstract

The microstructure of hydrogenation disproportionation desorption recombination processed powders with a nominal composition of Nd12.5Fe73Co8B6.5 was investigated by high resolution scanning electron microscopy and transmission electron microscopy. The Lorenz observation of the magnetic domain motion of various stages of the desorption recombination stage indicated that domain walls are strongly pinned by Nd-enriched grain boundaries in high coercivity powder.