【摘要】 采用传统烧结工艺制备了一组2∶17型烧结SmCo磁体。采用综合物性测量系统(PPMS)、洛伦兹透射电镜(LTEM)和微磁学计算研究了磁体的磁性能、磁畴结构及磁化过程中磁矩的变化过程。结果表明:经慢冷工艺的样品矫顽力为2180kA/m,磁畴壁沿1∶5相分布显示出明显的畴壁钉扎特性,未经慢冷工艺的样品矫顽力很低且磁畴壁呈直线型穿过2∶17相;经慢冷工艺的样品的Cu元素在1∶5相处富集使两相交界处磁晶各向异性降低;微磁学模拟计算证明1∶5相和2∶17相界面处对磁畴壁的吸引钉扎导致慢冷样品矫顽力的提高。更多还原

【Abstract】 A set of sintered Sm2Co17 magnets were prepared by conventional sintering process,then their hysteresis loops,magnetic domain structures and changes of magnetic moments during magnetization process were investigated by physical property measurement system(PPMS),Lorentz transmission electron microscopy(LTEM)and micromagnetic simulation,respectively.The results indicated that the sample treated by slow cooling process has a coercivity of 2180kA/m and magnetic domain walls distributing along the 1∶5phases,which shows obvious domain wall pinning properties,contrasting sharply with the remarkably low coercivity of the sample without slow cooling treatment and the"straight line"feature of magnetic domain walls running through 2∶17phases.We observed the Cu enrichment in 1∶5phases of the sample treated by slow cooling process,which attenuates interface magnetocrystalline anisotropy.A two-dimensional model was established through micromagnetic simulation,and the calculated changes of magnetic moments under different external magnetic fields confirmed the facilitating effect of attractive pinning by the interface between 1∶5and 2∶17phases on magnet′s coercivity.更多还原