表面活性剂辅助球磨制备具有强织构特征的纳米结构稀土永磁材料

Rare earth permanent magnet (REPM) with nanostructure has attracted much attention due to it can prepare high-performance nanocomposite magnets and soft/hard exchange coupled magnets. Furthermore, the surfactant-assisted ball milling (SABM) method is efficient in synthesis of single phase and textured nanostructured REPM compounds. However, this method still has many problems. The formation mechanism of nanostructures and the main role of surfactant are unclear. The size distribution is uneven for the as-prepared nanostructure. The surfactant is difficult to remove. The project is based on the character of surfactant, and will study the interaction mechanism between the surfactant and the materials and the relationship between the solvent and the surfactants with different hydrophilic-lipophilic balance, and confirm the the main role of surfactant. It is the theoretical guidance for exploring new surfactants and its removal method. In additions, by researching the influence of the magnetic interaction and the crystal structure (area of crystal plane) on the morphology and magnetic properties of the material during the ball milling process, and confirm the formation mechanism of nanostructures and texture. This research can promote preparation of the nanostructured REPM with high texture and controllable particle size, and make a contribution for development of our country REPM industry.

纳米结构的稀土永磁材料由于可以制备高性能的软/硬磁耦合磁体及高性能的纳米复合磁体而受到广泛关注。而表面活性剂辅助球磨又是一种高效制备单相、强织构纳米结构稀土永磁材料的方法。但是目前这一方法存在表面活性剂所起主要作用和织构的纳米结构形成机制不清，及制备的纳米结构粒度分布不均、表面活性剂去除困难等问题。本项目从表面活性剂的特点出发，通过研究不同种类、不同亲水亲油衡值的表面活性剂与材料及溶剂之间的相互关系，确定表面活性剂所起的主要作用，为探索新的表面活性剂及表面活性剂的去除提供理论指导；通过研究球磨过程中磁相互作用和晶体结构（晶面面积）对材料形貌及磁性能的影响，确定纳米结构及织构的形成机制，为制备高织构、粒度可控的纳米结构稀土永磁材料提供工艺方面的理论指导，也为我国稀土永磁事业的发展贡献一份力量。

纳米结构的稀土永磁材料由于可以制备高性能的软/硬磁耦合磁体及高性能的纳米复合磁体而受到广泛关注。表面活性剂辅助球磨是一种高效制备单相、强织构纳米结构稀土永磁材料的方法。但是目前这一方法存在制备的纳米结构粒度分布不均、表面活性剂去除困难等问题。本项目从表面活性剂的特点出发，在前期研究的基础上，创造性的使用了多步球磨及固体颗粒加表面表面活性剂共同辅助球磨的方式制备了高织构、超薄的SmCo5稀土永磁纳米片，这种纳米片相比于传统表面活性剂辅助球磨的方式，矫顽力提高了40%以上，对于后期制备烧结的纳米晶稀土永磁材料具有重要的意义。鉴于其创新的方法我们申请了2项专利，并于今年（2017年）全部授权，发表SCI论文5篇，其中影响因子大于3的论文3篇。为制备高织构、粒度可控的纳米结构稀土永磁材料提供了工艺方面的理论指导，也为我国稀土永磁事业的发展贡献一份力量。