添加稀土氢化物回收制备烧结钕铁硼及性能研究

Magnetic Properties of Regenerated Sintered NdFeB Magnets by Doping NdH3/PrH3 Powder

采用氢处理回收技术对废旧烧结钕铁硼磁体进行了回收制备,研究了不同含量的混合PrH3/NdH3氢化物对再生钕铁硼磁体性能的影响。通过全谱直读光谱仪、金相显微镜、磁测仪对再生磁体的组成、形貌及磁性能进行了表征。研究结果表明,最佳的氢处理工艺为在100℃、0. 1 MPa条件下吸氢,在600℃下脱氢;混合氢化物的掺入有效地改善了再生钕铁硼的组成结构。随着掺杂量的增加,再生磁体的富钕相体积不断增加,晶粒边界更为清晰,样品矫顽力持续增大,剩磁和最大磁能积未发生明显变化。确定了最佳的烧结温度和PrH3/NdH3氢化物掺杂量为1090℃和3%(质量分数),此条件下,样品相比原始磁体,剩磁回复96. 97%,矫顽力回复100. 21%,磁能积回复93. 25%。

Scrap sintered Nd-Fe-B magnets were recycled by using hydrogen decrepitation(HD) process. The effects of different content of mixed PrH3/Nd H3 powder on the properties of recycled Nd-Fe-B magnets were studied. Component,morphology and magnetic properties of the magnets were characterized by metallurgical microscope,inductively coupled plasma(ICP) spectroscopy and magnetometer. The results showed that the hydrogen decrepitation process is optimal when the hydrogenation is performed at 100 ℃ with 0. 1 MPa H2 pressure and dehydrogenation is performed at 600 ℃ . The composition of recycled magnets have been effectively improved by doping with different content of mixed PrH3/Nd H3 powder. With increasing of mixed PrH3/Nd H3 powder,Nd rich-phase and coercivity(Hcj) of the magnets gradually increase,and the grain boundary becomes more distinguishable. Meanwhile,the remanence(Br) and maximum energy product(BH)maxremained almost unchanged. Compared to the properties of the starting scrap sintered magnet,96. 97% of Br,100. 21% of Hcj and 93. 25% of(BH)maxhave been recovered in the recycled magnets sintered at 1090 ℃ with 3. 0 wt.% mixed PrH3/Nd H3 powder.