烧结Ce-Fe-B磁体的力学性能

发布时间：2018-04-16 19:40

  本文选题：烧结Ce-Fe-B磁体 + 力学性能　； 参考：《金属学报》2017年11期

【摘要】：以不同Ce含量的系列商业磁体(R_(1-x)Ce_x)_(30.5~31.5)Fe_(bal.)B_1M_1(质量分数,%)为研究对象,测试Ce-Fe-B磁体的抗弯强度、断裂韧性、硬度及脆性指数等性能,并对磁体的微观断口进行SEM和EDS分析。结果表明,含Ce磁体的抗弯强度和断裂韧性随Ce含量的增加呈减小的趋势,其Vickers硬度随Ce含量(x)的变化规律不明显。当x=0.15时,磁体力学性能出现极大值,磁体的抗弯强度、断裂韧性及脆性指数等力学指标均明显优于普通烧结Nd-Fe-B磁体;在此磁体中发现较多的"絮状"氧化物相存在,絮状相在裂纹扩展过程中会吸收一部分能量,可以缓解裂纹尖端的应力集中状态,因而起到强化和韧化的作用,对提高磁体的力学性能有利。当磁体中的Ce含量达到x=0.45时,磁体的力学性能明显变差,这是因为:此时磁体中有大晶粒出现,磁体的微观结构明显劣化。不同Ce含量磁体的断裂微观机制主要为沿晶断裂。
[Abstract]:Taking a series of commercial magnets with different ce content as the object of study, the properties of Ce-Fe-B magnets such as flexural strength, fracture toughness, hardness and brittleness index were tested, and the micro-fracture of the magnets was analyzed by SEM and EDS.The results show that the flexural strength and fracture toughness of ce containing magnets decrease with the increase of ce content, and the variation of Vickers hardness with ce content is not obvious.When x = 0.15, the mechanical properties of the magnets are maximized, and the mechanical properties of the magnets, such as bending strength, fracture toughness and brittleness index, are obviously superior to those of the ordinary sintered Nd-Fe-B magnets, and more "flocculent" oxide phases are found in the magnets.The flocculating phase absorbs some energy during crack propagation, which can alleviate the stress concentration state at the crack tip, so it plays the role of strengthening and toughening, which is beneficial to improve the mechanical properties of magnets.The mechanical properties of the magnets become worse when the content of ce in the magnets reaches x0. 45, which is due to the appearance of large grains in the magnets and the obvious deterioration of the microstructure of the magnets.The fracture mechanism of magnets with different ce content is mainly intergranular fracture.
【作者单位】： 钢铁研究总院功能材料研究所;宁波复能新材料有限公司;
【基金】：国家重点基础研究发展计划项目No.2014CB643701 国家自然科学基金重点项目No.51331003~~
【分类号】：TG132.27
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本文编号：1760309