中国物理B ›› 2024, Vol. 33 ›› Issue (10): 107506-107506.doi: 10.1088/1674-1056/ad6554
Yang Sun(孙洋)1,2, Ruoshui Liu(刘若水)3, Huayang Gong(宫华扬)2, and Baogen Shen(沈保根)1,2,3,4,†
Yang Sun(孙洋)1,2, Ruoshui Liu(刘若水)3, Huayang Gong(宫华扬)2, and Baogen Shen(沈保根)1,2,3,4,†
摘要: Ion substitution has significantly improved the performance of ferrite magnets, and cobalt remains a key area of research. Studies on the mechanism of Co$^{2+}$ in strontium ferrite, especially SrFe$_{2n-x}$Co$_{x}$O$_{19-\delta }$ ($n = 6.1$-5.4; $x = 0.05$-0.20) synthesized using the ceramic method, showed that Co$^{2+}$ preferentially enters the lattice as the Fe/Sr ratio decreases. This results in a decrease in the lattice constants $a$ and $c$ due to oxygen vacancies and iron ion deficiency. The impact of Co substitution on morphology is minor compared to the effect of the Fe/Sr ratio. As the Fe/Sr ratio decreases and the Co content increases, the saturation magnetization decreases. The magnetic anisotropy field exhibits a nonlinear change, generally increasing with higher Fe/Sr ratios and Co content. These changes in the performance of permanent magnets are attributed to the absence of Fe$^{3+}$ ions at the $12k + 2a$ and 2$b$ sites and the substitution of Co$^{2+}$ at the 2$b$ site. This suggests that by adjusting the Fe/Sr ratio and appropriate Co substitution, the magnetic anisotropy field of M-type strontium ferrite can be effectively optimized.
中图分类号: (Magnetic anisotropy)