Effects of terbium sulfide addition on magnetic properties,microstructure and thermal stability of sintered Nd-Fe--B magnets

• Published in: Chinese physics B 2016-07, Vol.25 (7), p.423-426
• Main Author: 李向斌 刘硕 曹学静 周贝贝 陈岭 闫阿儒 严高林
• Format: Article
• Language: English
• Subjects: 不可逆损失; 微观结构; 最大磁能积; 烧结钕铁硼磁体; 热稳定性; 矫顽力; 磁性能; 稀土硫化物
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/25/7/077502

To increase coercivity and thermal stability of sintered Nd–Fe–B magnets for high-temperature applications, a novel terbium sulfide powder is added into（Pr（0.25）Nd（0.75））（30.6）Cu（0.15）Fe（bal）B1（wt.%） basic magnets. The effects of the addition of terbium sulfide on magnetic properties, microstructure, and thermal stability of sintered Nd–Fe–B magnets are investigated.The experimental results show that by adding 3 wt.% Tb2S3, the coercivity of the magnet is remarkably increased by about 54% without a considerable reduction in remanence and maximum energy product. By means of the electron probe microanalyzer（EPMA） technology, it is observed that Tb is mainly present in the outer region of 2：14：1 matrix grains and forms a well-developed Tb-shell phase, resulting in enhancement of HA, which accounts for the coercivity enhancement.Moreover, compared with Tb2S3-free magnets, the reversible temperature coefficients of remanence（α） and coercivity（β） and the irreversible flux loss of magnetic flow（hirr） values of Tb2S3-added magnets are improved, indicating that the thermal stability of the magnets is also effectively improved.