摘要
采用晶间掺杂法,将纳米Al、Cu_(65)Ga_(35)与钕铁硼磁粉进行混合制备了烧结Nd-Fe-B磁体,研究了纳米Al及Cu_(65)Ga_(35)共掺杂对Nd-Fe-B磁体的磁性能、温度稳定性和微观结构的影响。结果表明:纳米Al与Cu_(65)Ga_(35)共掺杂有助于改善烧结Nd-Fe-B磁体的主相和富稀土相之间的浸润性,优化晶界富稀土相的分布,提高磁体的矫顽力,并改善磁体的温度稳定性。0.2 mass%纳米Al与0.1 mass%Cu_(65)Ga_(35)共掺杂制备的磁体具有最高的矫顽力,矫顽力由11.35 kOe提高到15.08 kOe,继续增加Cu_(65)Ga_(35)添加量会使磁体密度降低、孔洞增多,不利于矫顽力的提高。相较于未掺杂磁体,在20~100℃内,0.2 mass%纳米Al与0.1 mass%Cu_(65)Ga_(35)共掺杂的磁体剩磁温度系数由-0.115%/℃提高到-0.107%/℃,矫顽力温度系数由-0.736%/℃提高到-0.726%/℃,此外经过140℃保温2 h后,磁体的磁通不可逆损失由60.37%降低到39.98%。表明纳米Al及Cu_(65)Ga_(35)共掺杂可以减小磁体的磁通不可逆损失,改善磁体的热稳定性,有利于磁体在高温环境中的应用。
Sintered Nd-Fe-B magnets were prepared by mixing nano-Al, Cu_(65)Ga_(35) and Nd-Fe-B magnetic powder using intergranular doping method. The effect of nano-Al and Cu_(65)Ga_(35) co-doping on magnetic properties, temperature stability and microstructure of Nd-Fe-B magnets was investigated. The results show that the co-doping of nano-Al and Cu_(65)Ga_(35) can improve the wettability between the main phase and rare-earth rich phase of the sintered Nd-Fe-B magnet, optimize the distribution of rare-earth rich phase at the grain boundary, improve the coercivity and the temperature stability of the magnet. The magnet prepared by co-doping of 0.2 mass% nano-Al and 0.1 mass% Cu_(65)Ga_(35) has the highest coercivity, and the coercivity increases from 11.35 kOe to 15.08 kOe. Continuing to increase the amount of Cu_(65)Ga_(35) will reduce the magnet density and increase the holes, which is not conducive to the improvement of coercivity. Compared with undoped magnets, the remanence temperature coefficient of 0.2 mass% nano-Al and 0.1 mass% Cu_(65)Ga_(35) co-doped magnet increases from-0.115%/℃ to-0.107%/℃, and the coercivity temperature coefficient increases from-0.736%/℃ to-0.726%/℃ within the range of 20 ℃-100 ℃. In addition, after holding at 140 ℃ for 2 hours, the irreversible loss of magnetic flux of the magnet decreases from 60.37% to 39.98%. This work shows that the co-doping of nano-Al and Cu_(65)Ga_(35) can reduce the irreversible loss of magnetic flux and improve the thermal stability of the magnet, which is conducive to the application of the magnet in high temperature environment.
作者
李磊
李燊昊
张梦成
刘家琴
刘友好
衣晓飞
吴玉程
LI Lei;LI Shen-hao;ZHANG Meng-cheng;LIU Jia-qin;LIU You-hao;YI Xiao-fei;WU Yu-cheng(Institute of Industry and Equipment Technology,Anhui Province Key Laboratory of Areospace Structural Parts Forming Technology and Engineering,Hefei University of Technology,Hefei 230009,China;State Key Laboratory of Rare Earth Permanent Magnet Materials,Hefei 231500,China;Engineering Research Center of Advanced Composite Materials Design&Application of Anhui Province,Hefei 230051,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2022年第5期55-61,共7页
Transactions of Materials and Heat Treatment
基金
国家重点研发计划(2019YFF0217201)
安徽省科技重大专项(18030901098)
安徽省重点研发计划项目(202004b11020024,202104a05020019)。
