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（20届）本科毕业设计Nd-Fe-B稀土合金烧结组织矫顽力研究ResearchontheCoercivityofMicrostructuresofSinteredNdFeBRareEarthAlloy所在学院专业班级应用化学学生姓名学号指导教师职称完成日期年月I摘要【摘要】为了研究烧结温度、回火工艺对SPS烧结NdFeB磁体矫顽力的影响，本文利用扫描电子显微镜（SEM）、综合物理性能测试系统（PPMS）等仪器对磁体的组织与性能进行表征，并分析不同烧结温度与不同回火工艺对SPS烧结磁体磁性能和微观组织的影响，对比SPS烧结磁体与传统烧结磁体矫顽力与微观组织的不同之处。研究表明:SPSNdFeB磁体经不同回火制度后，磁性能都有不同程度的提高，经970℃×3h+600℃×2.5h回火后的SPS磁体磁性能提高幅度最大，矫顽力达到1120kA/m。通过观察微观组织，看到回火后的SPS磁体中出现短带状富钕相，比起颗粒状富Nd相，这样能够更好地起到磁隔离的作用。与同成分的传统烧结磁体相比，SPS磁体中薄带状的富Nd相相对比较少，导致磁隔离不足，因此SPS磁体矫顽力较传统烧结磁体较低。【关键词】NdFeB永磁材料；SPS;回火;矫顽力;微观结构IIResearchontheCoercivityandMicrostructureofNdFeBrareearthalloysinteredAbstract【ABSTRACT】：Inordertostudytheeffectofsinteringtemperature,andtemperingprocessonthecoercivityofNdFeBmagnets,withtheapplicationofSEMandPPMS,themagneticpropertiesandmicrostructureswerecharacteredinthispaper,andtheeffectofsinteringtemperatureamdtemperingprocessonmagneticpropertiesandmicrostructuresespeciallyontheboundaryphasewereanalyticed.Forethermore,wecomparedthepropertiesandmicrostructureofconventionalsinteredmagnetswithSPSsinteredmagnets.Theresultsshowthat,afterdifferenttemperingsystems,thepropertiesofSPSwereincreased;after970℃×3h+600℃×2.5htempering,thepropertiesimprovedsignificantly,thecoercivityofthemagnetswereincreasedto1120kA/m.Byobservingthemicrostructure,itwasfoundthatshortstrip-shapedNd-richphaseappearedintemperedSPSmagnets,itplayingaroleofisulation.Comparedwithconventionalsinteredmagnet,theSPSmagnetshavelessslice-likeNd-richphaseresultinginlowercoercivityfortheofmagneticisulation【KEYWORDS】：SPSNdFeBmagnets;tempering;coercivity;microstructuresIII目录1绪论.............................................................................................................................................................31.1钕铁硼永磁材料...............................................................................................................................31.1.1钕铁硼永磁材料概述...........................................................................................................21.1.2永磁材料的技术磁参量.......................................................................................................21.1.2.1钕铁硼永磁材料的矫顽力......................................................................................31.1.2.2剩磁Br………………………………………………………………………...……31.1.2.3最大磁能积（BH）max............................................................................................31.1.3影响NdFeB烧结磁体矫顽力的因素..................................................................................41.1.4钕铁硼永磁材料的微观相组成及其特征...........................................................................51.2放电等离子烧结(SparkPlasmaSintering，简称SPS)技术...........................................................51.2.1SPS技术的发展及应用.......................................................................................................51.2.2SPS基本装置......................................................................................................................51.2.3SPS技术的优点以及其在烧结稀土永磁材料上的应用....................................................61.3回火技术对烧结磁体矫顽力的影响...............................................................................................71.4本研究的主要背景、内容以及意义................................................................................................72实验过程及方法.......................................................................................................................................82.1样品制备...........................................................................................................................................82.2微观组织与磁性能表征...................................................................................................................92.2.1扫描电子显微镜(SEM)........................................................................................................92.2.2永磁材料高温测量系统.....................................................................................................102.2.3综合物理性能测试系统（PPMS）...................................................................................103实验结果与分析.....................................................................................................................................113.1烧结温度对矫顽力和微观结构的影响.........................................................................................113.1.1烧结温度对矫顽力的影响.................................................................................................113.1.2烧结温度对微观组织的影响.............................................................................................113.2不同回火工艺对矫顽力和微观组织的影响.................................................................................123.2.1不同回火工艺对矫顽力的影响.........................................................................................133.2.2不同回火工艺对微观组织的影响.....................................................................................133.3回火前后矫顽力和微观结构的差异.............................................................................................143.3.1回火前后矫顽力的差异........................................................................