Amorphous-crystalline state transformation induced by annealing in R sub(2)Fe sub(14)B (R = Nd, Er) compounds

Magnetization and neutron diffraction measurements have been carried out to study evolution of structure and magnetic states of amorphous Nd sub(2)Fe sub(14)B and Er sub(2)Fe sub(14)B alloys under isothermal annealing at 295-1025 K. The amorphization have been performed by neutron irradiation which provides a homogeneous state in different with other methods of amorphization. The annealing induces a rise of alpha -Fe phase content in alloys and a recrystallization into Nd sub(2)Fe sub(14)B-type phase. Neutron diffraction data show that the recrystallization occurs over narrow temperature interval (590-638) K in Er sub(2)Fe sub(14)B and at around 800 K in Nd sub(2)Fe sub(14)B. Magnetic measurements testify that in both samples the magnetization and coercive field increase with annealing temperature above 800 K.