中国物理B ›› 2010, Vol. 19 ›› Issue (6): 67504-067504.doi: 10.1088/1674-1056/19/6/067504
陈仁杰1, 李东1, 闫阿儒1, 刘壮2
Liu Zhuang(刘壮)a)b)†, Chen Ren-Jie(陈仁杰)a), Li Dong(李东)a), and Yan Ar-Ru(闫阿儒)a)
摘要: This paper reports that the SmCo6.8Zr0.2 nanocrystalline permanent magnets and SmCo6.8Zr0.2/\al-(Fe,Co) nanocomposite permanent magnets are successfully produced by mechanical alloying and subsequently annealing at 700~{^\circ}C for 10 minutes. The x-ray diffraction results show that the phase structure of SmCo6.8Zr0.2 nanocrystalline permanent magnets is composed of SmCo_{7} phase and SmCo6.8Zr0.2/\al-(Fe,Co) nanocomposite permanent magnets is composed of SmCo_{7} and α -(Fe,Co) phases. The mechanism of magnetization reversal is mainly controlled by inhomogeneous domain wall pinning in SmCo6.8Zr0.2 and SmCo6.8Zr0.2/\al-(Fe,Co) magnets. The inter-grain exchange interaction at low temperature is investigated, which shows that the inter-grain exchange interaction of SmCo6.8Zr0.2/\al-(Fe,Co) magnets increases greatly by the decrease of the measured temperature. According to \Delta m_{\rm irr}--H/H_{\rm cj}, \Delta m_{\rm rev}--H/H_{\rm cj} and \chi_{\rm irr}--H/H_{\rm cj} curves at room temperature and 100~K, the changes of irreversible and reversible magnetization behaviours of SmCo6.8Zr0.2 and SmCo6.8Zr0.2/\al-(Fe,Co) magnets with the decreasing temperature are analysed in detail. The magnetic viscosity and the activation volume of SmCo6.8Zr0.2 and SmCo6.8Zr0.2/\al-(Fe,Co) magnets at different temperatures are also studied.
中图分类号: (Magnetization reversal mechanisms)