Study of reversible changes of the coercive force of Nd-Fe-B- based alloys subjected to cyclic heat treatments

Results of the investigation of the reversibility of the magnetic properties of two Nd(Dy)-Fe(Co)-B alloys during cyclic treatments at temperatures of 1050-700°C and subsequent rapid cooling and annealing at 500-600°C are reported. It is shown that, after a significant decrease in the coercive force for magnetization (Hcm), which is caused by heating to high temperatures, its recovery begins after 5-min aging at 500°C; the complete restoration of Hcm takes place after 1-2 h exposure.