文章信息/Info

Title:

Rare Earth-based Permanent Nanomagnets: Materials Design, Chemical Synthesis and Magnetic Properties

作者:

侯仰龍; 楊文龍; 張會(huì)林

北京大學(xué)工學(xué)院

Author(s):

HOU Yanglong;  YANG Wenlong;  ZHANG Huilin

College of Engineering, Peking University

關(guān)鍵詞:

稀土永磁; 納米材料; 化學(xué)合成; 磁學(xué)性能

DOI:

10.7502/j.issn.1674-3962.2015.11.03

文獻(xiàn)標(biāo)志碼:

A

摘要:

隨著現(xiàn)代器件微型化、集成化的發(fā)展，具有高磁能積和優(yōu)異穩(wěn)定性的永磁材料得到了廣泛的應(yīng)用。材料的納米化及其組裝體構(gòu)建是實(shí)現(xiàn)該目標(biāo)的潛在途徑之一。利用硬磁材料高的磁晶各向異性能及軟磁材料高的飽和磁化強(qiáng)度，通過(guò)構(gòu)建硬磁-軟磁雙相耦合磁體，并同時(shí)實(shí)現(xiàn)硬磁、軟磁兩相磁反轉(zhuǎn)可有效提高材料的剩磁和飽和磁化強(qiáng)度，進(jìn)而顯著地增加材料的最大磁能積，為設(shè)計(jì)和制備新一代高性能磁體提供了重要途徑。液相化學(xué)法在單相永磁納米顆粒以及雙相耦合納米磁體制備方面均具有獨(dú)特的優(yōu)勢(shì)，在材料尺寸、組成、形貌及性能控制方面具有良好的可控性，具有重要的應(yīng)用價(jià)值。本文介紹了單相稀土永磁納米材料及硬磁-軟磁雙相耦合納米磁體的設(shè)計(jì)、化學(xué)合成及其磁學(xué)性能的最新研究進(jìn)展。

Abstract:

 With the development of modern technologies in integrated and miniaturized devices, permanent magnets with high energy products and impressive performances are needed. Fabrications and assemblings of nanostructured magnetic materials possess versatile prospects for applications. Next-generation permanent magnets can be fabricated utilizing nanoparticles as building blocks by exploiting nanoscale effects, especially by the exchange-coupled nanocomposites. A typical design of the nanocomposites made of fine mixture of magnetically hard and soft nanoparticles needs well-controlled compositions and interfaces, and vigorously enhances the magnetocrystalline anisotropy and the saturation magnetization. Chemical synthetic routes possess characteristic flexibilities on materials design, sizes, morphologies and self-assembled prospects. This review reports some representative studies on rare-earth magnetic nanomaterials and proposes some idealized nanocomposites for nanoparticle-based future permanent magnets with enhanced energy products.