摘要钕铁硼永磁材料是以硬磁相Nd2Fe14B为基础的化合物。通过微波烧结的方法使硬磁相Nd2Fe14B和软磁相ɑ-Fe在纳米范围内发生交换耦合效应，两相的边界可以连续性变化。通过改变烧结功率,微波加热时间不变和改变微波加热时间，烧结功率不变两种实验工艺方法，来获得每种合金在快淬条件下最佳磁性能和结构，从而得到优质的纳米复合永磁材料。本文将(Nd0.75Pr025)9Fe72Ti1Zr3MnxMo4-xB10.5C0.5(x=1，2，3)合金为原料，通过改变合金成分、微波烧结功率、微波加热时间三个工艺参数，来获得制备以上几种钕铁硼材料的最佳工艺参数。研究结果表明：微波热处理有利于调控软磁性相和硬磁性相之间的物相比例，进而有利于调节合金的综合磁性能。Mn元素比例的增加可以提高合金的非晶形成能力，当Mn和Mo元素的比例为1：1时，热稳定性达到最强。通过微波烧结工艺的探索，发现三种合金的最佳烧结功率均为2000W。58097

毕业论文关键词：合金成分；烧结温度；加热时间；磁性能

Abstract

NdFeB permanent magnet materials is based on Nd2Fe14B hard magnetic phase compounds. Through the method of microwave sintering, hard magnetic phase Nd2Fe14B and soft magnetic phase ɑ-Fe exchange coupling effect in nanometer scale, and the boundary of the two phase continuity can be changed. By microwave irradiation time on changing sintering power and power on sintering experiments of microwave irradiation time process, each alloy under the condition of rapid quenching can reach the best magnetic and structure, so as to get high quality nanocomposite permanent magnetic materials. In this article,   (Nd0.75Pr0.25)9Fe72Ti1Zr5MnxMo4-xB10.5C0.5(x=1,2,3) are raw material, by changing the alloy composition, power of microwave sintering and microwave heating time ,different series of nanocomposite permanent magnetic material was synthesized. Finally the optimum process parameters of the above several kinds of NdFeB material can be got. The results show that: microwave heat treatment is helpful to regulate the proportion of soft and hard magnetic phase, which is conducive to regulate alloy composite magnetic energy. The increase of Mn element proportion can improve the ability of the amorphous alloy formation .When the ratio of Mn and Mo element is 1:1, thermal stability can reach the strongest.Through the exploration of microwave sintering process, the best sintering power of  three alloys is 2000 W.

Key Words：alloying element; sintering temperature; heating time; magnetic properties

目录

1 绪论 1

1.1 材料 1

1.2 磁性材料 1

1.2.1 钕铁硼材料 2

1.3 纳米复合材料 2

1.4 纳米复合永磁材料的特征 3

1.5 交换耦合效应 4

1.6 纳米复合永磁材料的制备方法 5

1.6.1 HDRR方法 5

1.6.2 熔体快淬法 5

1.6.3 磁控溅射法 6

1.6.4 机械合金法 6

1.7 微量元素的添加对NdFeB纳米复合永磁材料的影响 6

1.8 烧结工艺 6

1.8.1 微波烧结 6

1.8.2 真空烧结 7

1.9 选题的目的和研究内容 7

1.9.1 实验机理 7