掺杂W型锶铁氧体的制备及磁性能研究

Studies on Preparation and Magnetic Properties of Doped W-type Strontium ferrites

采用柠檬酸溶胶-凝胶法制备了W型锶铁氧体SrZn_2Fe_(16)O_(27),研究了制备过程中柠檬酸用量、溶液pH、煅烧温度以及煅烧时间对纳米晶性能的影响。在此基础上,研究了掺钴SrZn_(2-x)Co_xFe_(16)O_(27) (x=0～1)对锶铁氧体磁性能的影响。试验结果表明,当柠檬酸与金属离子的摩尔比为1:1,溶液pH为6.0,烧结温度在1 100℃煅烧时间3 h时,得到粒径小、分散性好的纳米晶SrZn_2Fe_(16)O_(27)。并且,掺钴后随着掺杂量x的增大,比饱和磁化强度σ_s先增大后缓慢下降,而矫顽力Hc在x>0.2后明显下降,这非常有利于用作高密度磁记录材料。

W-type strontium ferrites are prepared by citric acid sol-gel method.The influence of citric acid,pH value,calcinations temperature and calcinations time are studied on the preparation process of SrZn_2Fe_(16)O_(27).Then,the magnetic properties of doped cobalt SrZn_2-xCoxFe_(16)O_(27) (x=0～1) are researched.The experi- mental results show that when the ratio of metal and citric acid is 1:1,pH is 6.0,calcinations temperature is 1100℃and calcina- tions time is 3 hours,the nanometers SrZn_2Fe_(16)O_(27) of small par- ticle size and perfect dispersivity are obtained.And the saturation magnetization os of SrZn_2-xCoxFe_(16)O_(27) increases at the begin- ning and then decreases slowly with increasing x,and coercive strength Hc is decreased obviously at x>0.2,which is very ben- eficial to high-density magnetic recording.