基于晶界调控的热变形纳米复合永磁取向及性能增强机制研究

项目名称： 基于晶界调控的热变形纳米复合永磁取向及性能增强机制研究

项目编号： No.51201191

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 金属材料学科

项目作者： 马毅龙

作者单位： 重庆科技学院

项目金额： 24万元

中文摘要： 如何实现全致密纳米复合永磁的硬磁相晶粒一致取向、并提高其磁性能和力学性能仍面临理论上和技术上的挑战。为此，申请者提出利用纳米晶Nd2Fe14B/α-Fe合金的晶界相调控，通过高熔点合金元素（铌和锆）添加以及低熔点金属（锌、铜、镓和铝）在热变形过程中的液相扩散，增强热变形磁体硬磁相取向能力，并改善微观结构和提高磁体性能。通过研究不同制备工艺下磁体的磁性能、力学性能及微观结构的变化，掌握以不同方式添加的合金元素对纳米复合永磁晶界相组成的影响规律，阐明晶界调控增强磁体取向及提高磁体磁性能和力学性能的机制；并进一步研究磁体磁畴结构变化以及磁化与反磁化过程，探讨晶界调控对热变形纳米复合磁体反磁化及矫顽力的影响机制。本项目为全致密各向异性纳米复合稀土永磁的制备及其硬磁相取向机理研究提供一种新思路，为改善其加工性能提供理论和实验基础，对新型高性能稀土永磁的设计、生产和应用具有重要的指导意义。

中文关键词： 各向异性；纳米晶钕铁硼；热压；磁性能；微观结构

英文摘要： There are still some technical and theoretical challenges to obatain the crystallographic alignment of hard magnetic phase and improve the magnetic properties and mechanical properties of bulk nanocomposite permanent magnets. In this research topic, the melt spun Nd2Fe14B/α-Fe alloy was selected as study subject with regard to its modification of the intergranular phase. Based on the addition of high-melting-point alloy （Nb and Zr） and the liquid diffusion of low-melting-point alloy (Zn,Cu,Ga and Al) in the processing, during which the crystallographic alignment of die-upset magnet was therefore enhanced, its microstructure and performance was improved. By the analysis of magnetic properties, mechanical properties and microstructure changes for the alloy under different preparation process, the effect mechanisms of alloy additives on its intergranular phase composition of the nanocomposite magnet were clarified, and the mechanism about the texture, magnetic and mechanical properties enhancement by the grain boundary control was illuminated. Based on further research on the magnetic domain structure and magnetization and reverse magnetization process, the effect mechanisms of the grain boundary control on the magnetization reversal and coercivity of the die-upset nanocomposite magnets was also explored. This stu

英文关键词： Anisotropic；nanocrystalline Nd-Fe-B；hot-pressing；magnetic properties；microstructure