The reaction mechanism of formation of chemically synthesized Nd2Fe14B hard magnetic nanoparticles

► The formation mechanism of Nd2Fe14B magnetic nanoparticles was studied. ► Nd2Fe14B phase formation occurs by two parallel competing reactions. ► Reaction of NdH2, Fe and B resulted in Nd2Fe14B phase formation. ► Nd2Fe14B phase can also be formed by the reaction of Nd2Fe17 and B. ► Maximum wt% of Nd2Fe14B phase was obtained at 800 °C and 90 min annealing.