Abstract
Ion substitution has significantly improved the performance of ferrite magnets,and cobalt remains a key area of research.Studies on the mechanism of Co2+in strontium ferrite,especially SrFe2n-xCoxO19-δ(n=6.1-5.4;x=0.05-0.20)synthesized using the ceramic method,showed that Co2+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 Fe3+ions at the 12k+2a and 2b sites and the substitution of Co2+at the 2b 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.
基金项目
Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E355B001)
Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3)
Science Center of the National Natural Science Foundation of China(52088101)
万方数据