Nd-Fe-B磁体晶界扩散Tb效果X射线荧光光谱法表征  

X-ray fluorescence spectrocopy characterization of grain boundary diffusion Tb effect for Nd-Fe-B magnet

作　　者：陈治安 金国顺 曹朔豪 陈国安 CHEN Zhi-an;JIN Guo-shun;CAO Shuo-hao;CHEN Guo-an(Reliability Laboratory,Beijing Zhong Ke San Huan Hi-Tech Co,Ltd,Beijing 102200,China;SANVAC Beijing Magnetics Co,Ltd,Beijing 102200,China)

机构地区：[1]北京中科三环高技术股份有限公司信赖性实验室,北京102200 [2]三环瓦克华(北京)磁性器件有限公司,北京102200

出　　处：《磁性材料及器件》2024年第5期25-31,共7页Journal of Magnetic Materials and Devices

基　　金：国家重点研发计划项目(2022YFB3505400)。

摘　　要：采用能量散射X射线荧光光谱法(ED-XRF)对晶界扩散(GBD)Tb元素的烧结Nd-Fe-B磁体的扩散效果进行评价。通过对比分析,发现ED-XRF法、辉光放电光谱法(GD-OES)和能谱法(EDS)都可以表征扩散元素Tb含量的深度分布特征,而ED-XRF法的检测特征和检测斑的尺寸等参数更适用于评价选区扩散磁体的扩散效果。当对样品扩散区域的局部位置进行不同深度多次测量时,相对于GD-OES法,采用ED-XRF法对测量深度的表征更为合理。数据显示大部分扩散元素Tb聚集在磁体表层约200μm范围内,而对磁体整体矫顽力提高起到显著作用的扩散量的临界值远小于磁体表层的Tb含量。另外,发现表面涂覆不同厚度富Tb扩散源的Nd-Fe-B磁体在经历相同热处理参数GBD工艺后,内部Tb元素含量出现差异性分布。同时还分析了采用硝酸溶液酸洗减薄法制备XRF样品的可行性,数据显示相比于双面磨或机械切割,使用硝酸溶液酸洗法制样显得更为方便且对减薄量的选择更自由。In this work,the diffusing result of the grain boundary diffusion(GBD)Nd-Fe-B sintered magnets had been evaluated applying the energy dispersive X-Ray fluorescence spectroscopy(ED-XRF)technique.It was found that,after comparative analysis,the depth distribution of Tb content can be analyzed by all the three methods:EDS,GD-OES and EDXRF.Compared to the two other methods,ED-XRF method is considered more suitable to evaluate the diffusing result due to its technique theory and parameter such as the size of the measurement-spot.Most of the Tb distributed in the surfacelayer with the depth range of 0 to 200μm.What’s more,the critical Tb content resulting to the drastic enhancement of coercivity is probably much lower than the Tb content in the surface-layer of the GBD magnets.Different characteristics of the Tb-distribution were displayed for the samples with different thickness of diffusion-source layer.In addition,as one of the sample-preparation methods,pickling thinning method is more flexible than some mechanical methods to make the sample for ED-XRF measurement.

关 键 词：烧结ND-FE-B磁体 晶界扩散 X射线荧光光谱法 Tb深度分布特征 

分 类 号：TM273[一般工业技术—材料科学与工程]