【作者】 谢国治； 王泽华； 吴玉萍； 林萍华； 顾本喜； 鹿牧； 都有为； 袁钻如；

【Author】 XIE Guo-zhi, WANG Ze-hua, WU Yu-ping, LIN Ping-hua, GU Ben-xi,LU Mu, DU You-wei, YUAN Zuan-ru(Department of Materials Science and Engineering, Hohai University, Nanjing 210024, China;National Lab. of Solid State Microstructures, Physics Dep. of Nanjing University.Nanjing 210093, China;Modern Analytical Center, Nanjing University, Nanjing 210093, China)

【机构】 河海大学材料科学与工程系； 固体微结构国家重点实验室南京大学 物理系； 南京大学现代分析中心；

【摘要】 在前期研究工作的基础上,从热磁重(TMA)测量出发对快淬Nd9Fe85-xMnxB6(x=0-2)的相关磁性能及交换耦合效应作了进一步的研究.发现在最佳的热处理条件下,一定的Mn掺杂能提高快淬NdFeB的磁性能,特别是矫顽力最大能提高20%左右,但是更高的Mn掺杂量会导致矫顽力和最大磁能积的明显下降.XRD显示快淬态的NdFeB样品的晶化程度随Mn掺杂量提高而提高,但在最佳的热处理条件下所有的快淬NdFeB样品都包括硬磁性相Nd2Fe14B和软磁性相α-Fe.热磁重(TMA)测量显示一直随着Mn掺杂量提高到2%(原子分数),硬磁性相Nd2Fe14B的居里温度(Tc)在不断下降,但是α-Fe的Tc却随Mn掺杂量提高而提高.认为磁性能和居里温度改变是因为形成了δ-Mn和R2Fe23B3相.当Mn掺杂量较低时高温下有δ-Mn形成并和α-Fe产生交换耦合作用导致α-Fe的居里温度升高,而当Mn掺杂量提高到2at%时形成的R2Fe23B3相固溶δ-Mn相才导致α-Fe的居里温度下降.更多还原

【Abstract】 A study on the magnetic properties of Nd9Fe85-xMnxB6 (x=0-2) melt-spun ribbons has been investigated. Under optimal heating condition, it was found that an appropriate amount of Mn could enhance hard magnetic properties, especially the maximum coercivity, which increases more than about 20%. Higher amounts of Mn addition lead to a loss of coercivity and (BH)max. XRD results indicate that each of alloys consists of hard magnetic Nd2Fe14B phase and soft magnetic α -Fe phase. TMA scans indicate that the Curie temperature (Tc) of a -Fe phase rises with the Mn doping content increasing until x=2. For x=2 sample there is a slope between the Nd2Fe14B phase and α -Fe phase peaks in TMA curve. It can be attributed to the formation of the metastable Nd2Fe23B3 phase. The change of magnetic properties and the Curie temperature may be attributed to the formation of 8-Mn and R2Fe23B3 phase.更多还原