Preparation and Properties Investigation of Neutron Absorber Material Fe-TbFeO₃-DyFeO₃

Fe-TbFeO₃-DyFeO₃ was prepared by powder metallurgy technology. The microstructures of ball milled powder mixtures and sintered bulks were analyzed by X-ray diffraction, scanning electron microscope and transmission electron microscope. Thermophysical properties, corrosion resistance and ion irradiation properties of the sintered Fe-TbFeO₃-DyFeO₃ bulks were measured and analyzed. The experiment results show that the homogeneous nanocrystalline Fe-Tb₄O₇-Dy₂O₃ powder mixtures are obtained by ball milling. Tb₄O₇ transforms to Tb₂O₃ at high temperature. Contents of Tb₂O₃ and Dy₂O₃ decrease with temperature increase during sintering process, andFe-TbFeO₃-DyFeO₃ bulks are obtained after sintering at 1200 ℃ for 24 h. The bulks have high thermal conductivity, low thermal expansion coefficient and poor corrosion resistance performance. The sintered bulks are irradiated at 400-600 ℃ for 25 dpa. It is found that the irradiation swelling rate decreases with temperature increase, and the maximum swelling rate is 0.5% at 400℃.