摘要
采用直流(DC)磁控溅射的方法,在烧结NdFeB磁体表面制备了DyAl合金薄膜,镀膜样品经真空热扩渗(800℃×6h)和时效处理(900℃×2.5h+490℃×5h),研究了样品的微观结构组织与磁性,并对Dy、Al元素在基体中的真空热扩渗行为进行了探讨。结果表明,随着DyAl合金薄膜厚度的增加,磁体的内禀矫顽力Hcj相应提高,内禀矫顽力Hcj提高176kA/m(2.2kOe)。通过对样品微观组织结构观察发现,Dy和Al元素沿晶界富Nd相优先扩散,大量集中分布在主相晶粒表层和富Nd相交界处,不仅改善了晶界表面浸润性,也改变了主相晶粒表层合金成分和微结构,这种晶粒表面与晶界相的改性导致烧结NdFeB磁体的内禀矫顽力Hcj提高。
DyAl alloy film was deposited on the surface of sintered NdFeB magnet by the method of DC magnetron sputtering,and the samples were treated by vacuum diffusing and aging treatment.Microstructure and magnetic properties of the samples were studied.The results show that the intrinsic coercivity was improved with thickness increasing of the DyAl alloy film,and the intrinsic coercivity increased 176kA/m（2.2kOe）.The microstructure analysis shows that Dy and Al firstly diffused along the grain boundary of Nd-rich phase,and were mostly distributed at the junction of the grain surface and Nd-rich phase,that not only improved the ability of the grain surface infiltration but also changed the composition and microstructure of main grain surface,so that this kind modification of grain surface and boundary phase leads to improving of the heat resistance of sintered NdFeB.
出处
《稀土》
EI
CAS
CSCD
北大核心
2010年第4期17-20,共4页
Chinese Rare Earths
