First principles study of transition-metal substitutions in Sm–Co permanent magnets
First principles study of transition-metal substitutions in Sm–Co permanent magnets
复制标题
DOI：
10.1063/1.1792791
复制
发表时间：
2004-09
影响因子：
4
通讯作者：
R. Sabirianov;A. Kashyap;R. Skomski;S. Jaswal;D. Sellmyer
中科院分区：
文献类型：
--
作者：
R. Sabirianov;A. Kashyap;R. Skomski;S. Jaswal;D. Sellmyer
用第一性原理计算方法研究了常规和高温Sm-Co永磁体的微观化学和磁性。特别强调的是在SmCo 5和Sm 2Co 17化合物中Cu，Ti和Zr的取代的位置偏好。Cu替代在1：5相中更有利，与实验结果一致。钛和锆对于两相都具有正的溶解能，其中Ti（Zr）对于1：5（2：17）相具有轻微的偏好。由于Zr具有较大的固溶能，部分Zr可能偏聚到相界。对于Ti和Zr的哑铃网站的2：17相是优选的其他三个不等价的钴网站。这些结果被用来讨论所观察到的蜂窝状纳米结构的高温Sm-Co硬磁体的组成接近2：17相。
The microchemistry and magnetism of conventional and high-temperature Sm–Co permanent magnets are investigated by first-principles calculations. Particular emphasis is on the site preference for the substitution of Cu, Ti, and Zr in SmCo5 and Sm2Co17 compounds. Cu substitution is more favorable in the 1:5 phase, in agreement with experimental findings. Titanium and zirconium have positive solution energies for both the phases, with Ti(Zr) having slight preference for the 1:5 (2:17) phase. Some Zr may segregate to the phase boundaries because of its large solution energy. For Ti and Zr the dumbbell site of the 2:17 phase is preferred over the other three inequivalent cobalt sites. These results are used to discuss the observed cellular nanostructure of the high-temperature Sm–Co hard magnets with composition close to the 2:17 phase.