放电烧结制备Nd_2Fe_(14)B/α-Fe纳米晶双相复合永磁研究  

Nd_2Fe_(14)B/α-Fe Nanocomposite Permanent Magnets Produced by Spark Plasma Sintering

作　　者：牛培利[1] 岳明[1] 张东涛[1] 张久兴[1] 

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100022

出　　处：《北京工业大学学报》2007年第6期622-626,共5页Journal of Beijing University of Technology

基　　金：国家自然科学基金(50201001);北京市自然科学基金重点项目资助项目(2041001).

摘　　要：采用放电等离子烧结技术制备了热压/热变形Nd_2Fe_(14)B/α-Fe纳米双相复合永磁,研究了不同烧结条件对热压磁体致密度和性能的影响,以及热变形工艺对磁体微观结构及磁性能的影响．结果表明,随着热压温度的升高,磁体的密度和剩磁逐渐增大,矫顽力呈降低趋势,最大磁能积随温度的变化先升高后降低,最大值为94．7 kJ/m^3．热变形后样品内Nd_2Fe_(14)B主相晶粒的〈OOL〉轴逐渐转向与压力平行的方向,形成磁晶各向异性,但同时由于缺乏富Nd相及晶粒过度长大,磁性能呈下降趋势．The hot pressing and hot deforming Nd2Fe14B/α-Fe nanocomposites were produced by Spark Plasma Sintering technique. Effects of pressing conditions of the microstructure and magnetic properties of themagnets were investigated. The results show that with the increase of hot press temperature, the density and the remanence of the magnets increase, while the coercivity decreases gradually, which leads to the rising of the energy at first and then decreasing. The maxium was at 94.7 kJ/m^3. After hot deformation, the （00L）axis of Nd2Fe14B crystalline turned parallel to the direction of compressive pressure, thereby the magnetic anisotropic magnets were gained. However, the grain size became quite large due to high deforming temperature, therefore, the magnetic properties reduced sharply accordingly.

关 键 词：Nd2Fe14B/α—Fe 热变形 各向异性 放电等离子烧结 

分 类 号：TM274[一般工业技术—材料科学与工程]