Progress of Sm-Fe-N Anisotropic Magnets
A reduction and diffusion method (R/D) is used to make a mother alloy of Sm-Fe-N anisotropic magnets. Reduction of 0.5wt％ of samarium content compared to the conventional powder increases magnetization. Milling condition and surface treatment improve the squareness of demagnetization curve, the aging property and the heat resistance. The maximum energy product of 292 kJ/m3 is obtained with the powder. High coercive force is maintainable even if the powder is exposed for 300h in 80 ℃ 90％RH. The maximum energy product of 141 kJ/m3 is obtained with an injection molded anisotropic magnet. The aging property estimated by irreversible flux loss is comparable to the conventional MQP-B magnets. The heat resistance temperature (T_5％) at which the initial irreversible flux loss becomes -5％ is 125-more than 150 ℃ for Sm-Fe-N magnets and 150-170 ℃ for hybrid magnets. The magnetic properties of bonded HDDR Nd-Fe-B magnet were improved by substituting for Nd-Fe-B powder with Sm-Fe-N powder. A new technology to make anisotropic bonded Sm-Fe-N thin cylinder magnets by an injection molding using unsaturated polyester (UP) resin was developed.
bonded Sm-Fe-N anisotropic magnet reduction diffusion injection
Kenji Ohmori Takashi Ishikawa
Sumitomo Metal Mining Co., Ltd., Ichikawa, Chiba 272-8588, Japan
国际会议
北京
英文
221-230
2006-08-29（万方平台首次上网日期，不代表论文的发表时间）