Preparation and properties of hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders

• 作者: Peng Zhao Yang Luo Dun-Bo Yu Hai-Jun Peng Wen-Long Yan Zi-Long Wang Xin-Yuan Bai
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 2033-2039
• 页数: 7页
• 语种: 英文

摘要

The hot-deformed magnets processed from nanocrystalline/amorphous Nd-Fe-B powders were pre-pared under different hot-pressing temperatures(600-750 ℃,at intervals of 25 ℃) by the self-made hot-pressing equipment.The microstructure and magnetic properties of hot-deformed magnets prepared at different temperatures were also investigated.When the temperature is above 650 ℃,the density of magnet reaches 7.5 g·cm-3.The optimum magnetic properties of magnetic induction intensity of Br =1.3 T,optimum energy product of(BH)max =282.5 kJ·m-3,intrinsic coercivity of Hcj =1130.0 kA·m-1 of hot-deformed magnets are obtained at hot-pressing temperature of 650 ℃.X-ray diffractometer pattern shows that the (00L) texture has been obtained.For the microstructural characteristic,on the one hand,the good magnetic performance is attributed to the fine platelet-like grains with an average length of 410-440 nm at the hot-pressing temperature range from 625 to 675 ℃.On the other hand,the unaligned coarse grains are observed in all the samples.And the areal fraction of those is gradually increasing with the rise of the hot-pressing temperature,which tends to deteriorate the magnetic properties.The composition map shows the accumulation of Nd/Pr-rich phase in the coarse grains' region.