添加MgF_2对烧结NdFeB磁体的性能和微观组织的影响Effects of MgF_2 on Properties and Microstructure of Sintered NdFeB Magnets
徐芳;董显平;张澜庭;刘琼珍;王静;吴建生;
摘要(Abstract):
采用晶界添加MgF2制备烧结NdFeB磁体,通过扫描电镜、透射电镜和性能测试,研究了烧结NdFeB磁体的微观组织及其对磁性能、电阻率的提高和耐腐蚀性能的影响。结果表明:添加适量MgF2可实现在磁体剩磁、矫顽力和电阻率提高的基础上,同时提高材料的腐蚀电位,并且在极化曲线的阳极部分相同电位条件下,具有较小的极化电流密度,从而达到改善NdFeB磁体耐腐蚀性能的目的。磁体显微组织研究表明F元素进入晶界相,形成F含量约为30%(原子分数)、以面心立方为基的有序的NdOxFy相,其与磁性能、电阻率的提高和耐腐蚀性能改善有关。
关键词(KeyWords): NdFeB磁体;磁性能;电阻率;抗腐蚀性能;NdOxFy相;稀土
基金项目(Foundation): 上海应用材料研究与发展基金(08520740200)资助
作者(Author): 徐芳;董显平;张澜庭;刘琼珍;王静;吴建生;
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